French
DeutschList of submarines of World War II
This is a list of submarines of World War II, which began with the German invasion of Poland on 1 September 1939 and ended with the surrender of Japan on 2 September 1945.
Germany used submarines to devastating effect in the Battle of the Atlantic, where it attempted to cut Britain's supply routes by sinking more merchant ships than Britain could replace. While U-boats destroyed a significant number of ships, the strategy ultimately failed. Although U-boats had been updated in the interwar years, the major innovation was improved communications and encryption; allowing for mass-attack naval tactics. By the end of the war, almost 3,000 Allied ships (175 warships, 2,825 merchantmen) had been sunk by U-boats.[1]
The Imperial Japanese Navy operated the most varied fleet of submarines of any navy, including Kaiten crewed torpedoes, midget submarines (Type A Ko-hyoteki and Kairyu classes), medium-range submarines, purpose-built supply submarines and long-range fleet submarines. They also had submarines with the highest submerged speeds (I-201-class submarines) and submarines that could carry multiple aircraft (I-400-class submarines). They were also equipped with one of the most advanced torpedoes of the conflict, the oxygen-propelled Type 95.
The submarine force was the most effective anti-ship weapon in the United States Navy arsenal. Although constituting only about 2 percent of the U.S. naval force, submarine force destroyed over 30 percent of the Imperial Japanese Navy, and over 60 percent of the Japanese merchant fleet, The Royal Navy Submarine Service was used primarily to blockade trade and military supply routes to Africa and the Near and Far East, but also obtained the only mutually submerged submarine-to-submarine combat kill of World War II. This occurred when the crew of HMS Venturer engaged the U-864, manually computed a successful firing solution against a three-dimensional moving target using techniques which became the basis of modern torpedo computer targeting systems.[2][3][4][5]
Excluding special underwater craft such as midget submarines, the German Kriegsmarine lost 765 submarines to all causes during World War II[6] in addition to 150 submarines scuttled in German-held ports in northern Europe during the first week of May 1945 by their crews to avoid surrendering them to the Allies,[7] while Japan lost 129 submarines[8] and Italy 91.[9] The Royal Navy lost 73[10] and the U.S. Navy 52 submarines,[11][12][13][14] while France lost 59.[15] The Soviet Union′s submarine losses are not necessarily fully known, but the Soviet Navy probably lost 98 submarines.[15]
Submarines show submerged displacement in long tons.
| Name | Operator | Class | Type | Submerged displacement (long tons) | First commissioned | Fate |
|---|---|---|---|---|---|---|
| Acciaio |  Regia Marina | Acciaio | coastal submarine | 864 | 30 October 1941 | Sunk 13 July 1943 |
| Achéron |  French Navy | Redoutable | cruiser submarine | 1,968 | 22 February 1932 | Scuttled 27 November 1942; refloated July 1943; sunk 24 November 1943 |
| Achille | 29 June 1933 | Scuttled 18 June 1940 | ||||
| Actéon | 18 December 1931 | Sunk 8 November 1942 | ||||
| Adua | Regia Marina | Adua | coastal submarine | 843 | 14 November 1936 | Sunk 30 September 1941 |
| Agosta | French Navy | Redoutable | cruiser submarine | 1,968 | 1 February 1937 | Scuttled 18 June 1940 |
| Ajax | 1 February 1934 | Scuttled 24 September 1940 | ||||
| Alabastro | Regia Marina | Acciaio | coastal submarine | 864 | 9 May 1942 | Sunk 14 September 1942 |
| Alagi | Adua | coastal submarine | 843 | 6 March 1937 | Sold for scrap 1 February 1948 | |
| Alessandro Malaspina | Marconi | submarine | 1,490 | 20 June 1940 | Missing after 7 September 1941 | |
| Alpino Bagnolini | Liuzzi | submarine | 1,484 | 22 December 1939 | Seized by Germany September 1943; renamed UIT-22; sunk 11 March 1944 | |
| Amazone | French Navy Free French Naval Forces | Diane | submarine | 796 | 12 October 1933 | Stricken 26 April 1946 |
| Amberjack |  United States Navy | Gato | fleet submarine | 2,424 | 19 June 1942 | Sunk 16 February 1943 |
| Ambra | Regia Marina | Perla | coastal submarine | 839 | 4 August 1936 | Sunk 4 September 1944 |
| Ametista | Sirena | coastal submarine | 837 | 1 April 1934 | Scuttled 12 September 1943 | |
| Ammiraglio Cagni | Cagni | submarine | 2,136 | 1 April 1941 | Stricken 1 February 1948 | |
| Ammiraglio Caracciolo | 1 June 1941 | Scuttled 11 December 1941 | ||||
| Ammiraglio Millo | 1 May 1941 | Sunk 14 March 1942 | ||||
| Ammiraglio Saint-Bon | 12 June 1941 | Sunk 5 January 1942 | ||||
| Amphion |  Royal Navy | Amphion | submarine | 1,590 | 27 March 1945 | Sold for scrap 24 June 1971 |
| Amphitrite | French Navy | Diane | submarine | 796 | 8 June 1933 | Sunk 8 November 1942 |
| Anfitrite | Regia Marina | Sirena | coastal submarine | 837 | 22 March 1934 | Sunk 6 March 1941 |
| Angler | United States Navy | Gato | fleet submarine | 2,424 | 1 October 1943 | Sold for scrap 1 February 1974 |
| Antiope | French Navy Free French Naval Forces | Diane | submarine | 796 | 12 October 1933 | Stricken 26 April 1946 |
| Antonio Sciesa | Regia Marina | Balilla | cruiser submarine | 1,874 | 12 April 1929 | Scuttled 12 November 1942 |
| Apogon | United States Navy | Balao | fleet submarine | 2,391 | 16 July 1943 | Sunk as target 25 July 1946 |
| Aradam | Regia Marina | Adua | coastal submarine | 843 | 16 January 1937 | Scuttled September 1943; refloated by Germany; sunk 4 September 1944 |
| Archerfish | United States Navy | Balao | fleet submarine | 2,391 | 4 September 1943 | Sunk as target 19 October 1968 |
| Archimède | French Navy Free French Naval Forces | Redoutable | cruiser submarine | 1,968 | 22 December 1932 | Scrapped February 1952 |
| Archimede | Regia Marina | Brin | submarine | 1,380 | 18 April 1939 | Sunk 15 April 1943 |
| Aréthuse | French Navy Free French Naval Forces | Argonaute | submarine | 785 | 14 July 1933 | Joined the Free French Naval Forces December 1942; laid up 1944; sold for scrap 25 March 1946 |
| Argento | Regia Marina | Acciaio | coastal submarine | 864 | 16 May 1942 | Scuttled 3 August 1943 |
| Argo | French Navy Free French Naval Forces | Redoutable | cruiser submarine | 1,968 | 12 February 1933 | Scrapped April 1946 |
| Argo | Regia Marina | Argo | coastal submarine | 1,000 | 31 August 1937 | Scuttled 10 September 1943; refloated by Germany; scuttled 1 May 1945 |
| Argonaut (SS-166) | United States Navy | V-4 | submarine | 4,161 | 2 April 1928 | Sunk 10 January 1943 |
| Argonaut (SS-475) | Tench | fleet submarine | 2,414 | 15 January 1945 | Sold to Canada as HMCS Rainbow 1968, scrapped 1977 | |
| Argonauta | Regia Marina | Argonauta | coastal submarine | 1,080 | 1 January 1932 | Sunk 28 June 1940 |
| Argonaute | French Navy | Argonaute | submarine | 785 | 1 June 1932 | Sunk 8 November 1942 |
| Ariane | Ariane | submarine | 787 | 1 September 1929 | Scuttled 9 November 1942 | |
| Ascianghi | Regia Marina | Adua | coastal submarine | 843 | 25 March 1938 | Sunk 23 July 1943 |
| Aspro | United States Navy | Balao | fleet submarine | 2,391 | 31 July 1943 | Sunk as target 16 November 1962 |
| Asteria | Regia Marina | Acciaio | coastal submarine | 864 | 8 November 1941 | Scuttled 17 February 1943 |
| Astute | Royal Navy | Amphion | submarine | 1,590 | 30 June 1945 | Sold for scrap 1 October 1970 |
| Atalante | French Navy Free French Naval Forces | Argonaute | submarine | 785 | 18 September 1934 | Joined the Free French Naval Forces December 1942; laid up 1944; sold for scrap 25 March 1946 |
| Atropo | Regia Marina | Foca | minelayer submarine | 1,625 | 14 February 1939 | Stricken 23 March 1947 |
| Atule | United States Navy | Balao | fleet submarine | 2,391 | 21 June 1944 | Transferred to Peru as Pacocha 31 July 1974; sunk in collision 26 August 1988 |
| Aurore | French Navy | Aurore | coastal submarine | 1,150 | 20 June 1940 | Scuttled 27 November 1942 |
| Avorio | Regia Marina | Acciaio | coastal submarine | 864 | 25 March 1942 | Scuttled 8 February 1943 |
| Axum | Adua | coastal submarine | 843 | 2 December 1936 | Wrecked and scuttled 28 December 1943 | |
| Balao | United States Navy | Balao | fleet submarine | 2,391 | 4 February 1943 | Sunk as target 6 September 1963 |
| Balilla | Regia Marina | Balilla | cruiser submarine | 1,874 | 21 July 1928 | Decommissioned 28 April 1941, converted into barge, scrapped 1946 |
| Bang | United States Navy | Balao | fleet submarine | 2,391 | 4 December 1943 | Transferred to Spain as Cosme Garcia, 1 October 1972; scrapped 1983 |
| Barb | Gato | fleet submarine | 2,424 | 2 April 1942 | Sold to Italy as Enrico Tazzoli 13 December 1954, scrapped 1973 | |
| Barbarigo | Regia Marina | Marcello | submarine | 1,313 | 19 September 1938 | Missing after 16 June 1943 |
| Barbel | United States Navy | Balao | fleet submarine | 2,391 | 3 April 1944 | Sunk 4 February 1945 |
| Barbero | 29 April 1944 | Sunk as target 7 October 1964 | ||||
| Barracuda | Barracuda | submarine | 2,506 | 1 October 1924 | Sold for scrap 16 November 1945 | |
| Bashaw | Gato | fleet submarine | 2,424 | 25 October 1943 | Sold for scrap 4 August 1972 | |
| Bass | Barracuda | submarine | 2,506 | 26 September 1925 | Scuttled 12 March 1945 | |
| Batfish | Balao | fleet submarine | 2,391 | 21 August 1943 | Museum ship 18 February 1972 | |
| Baya | 20 May 1944 | Sold for scrap 12 October 1973 | ||||
| Becuna | 27 May 1944 | Museum ship 21 June 1976 | ||||
| Beilul | Regia Marina | Adua | coastal submarine | 843 | 14 September 1938 | Captured by Germany 9 September 1943; Sunk May 1944 |
| Bergall | United States Navy | Balao | fleet submarine | 2,391 | 12 June 1944 | Transferred to Turkey as Turgutreis 18 October 1958; scrapped April 2000 |
| Berillo | Regia Marina | Perla | coastal submarine | 846 | 5 August 1936 | Scuttled 2 October 1940 |
| Besugo | United States Navy | Balao | fleet submarine | 2,391 | 19 June 1944 | Transferred to Italy as Francesco Morosini 31 May 1966; sold for scrap, 20 June 1977 |
| Bévéziers | French Navy | Redoutable | cruiser submarine | 1,968 | 4 June 1937 | Sunk 5 May 1942 |
| Billfish | United States Navy | Balao | fleet submarine | 2,391 | 20 April 1943 | Sold for scrap 17 March 1971 |
| Blackfin | 4 July 1944 | Sunk as target 13 May 1973 | ||||
| Blackfish | Gato | fleet submarine | 2,424 | 22 July 1942 | Sold for scrap on 4 May 1959 | |
| Blenny | Balao | fleet submarine | 2,391 | 27 June 1944 | Scuttled 7 June 1989 | |
| Blower | 10 August 1944 | Transferred to Turkey as Dumlupınar 16 November 1950; sunk in collision 4 April 1953 | ||||
| Blueback | 28 August 1944 | Transferred to Turkey as İnönü 23 May 1948; returned to United States for scrapping 30 November 1973 | ||||
| Bluefish | Gato | fleet submarine | 2,424 | 24 May 1943 | Sold for scrap 8 June 1960 | |
| Bluegill | fleet submarine | 2,424 | 11 November 1943 | Scuttled 3 December 1970 | ||
| Boarfish | Balao | fleet submarine | 2,391 | 23 September 1944 | Transferred to Turkey as Sakarya 23 May 1948; returned to United States for scrapping 1 January 1974 | |
| Bonefish | Gato | fleet submarine | 2,424 | 31 May 1943 | Sunk 18 June 1945 | |
| Bonita | Barracuda | submarine | 2,506 | 22 May 1926 | Sold for scrap 4 October 1945 | |
| Bowfin | Balao | fleet submarine | 2,391 | 1 May 1943 | Museum ship 1 August 1979 | |
| Bream | Gato | fleet submarine | 2,424 | 24 January 1944 | Sunk as target 7 November 1969 | |
| Brill | Balao | fleet submarine | 2,391 | 26 October 1944 | Transferred to Turkey as Birinci İnönü 25 May 1948; decommissioned 29 November 1972 | |
| Brin | Regia Marina | Brin | submarine | 1,380 | 18 April 1939 | Stricken 1 February 1948 |
| Bronzo | Regia Marina | Acciaio | coastal submarine | 864 | 2 January 1942 | Captured by Royal Navy 12 July 1943; commissioned as HMS P714; transferred to France as Narval 29 January 1944; scrapped 1948 |
| Bugara | United States Navy | Balao | fleet submarine | 2,391 | 15 November 1944 | Sank under tow 1 June 1971 |
| Bullhead | 4 December 1944 | Sunk 6 August 1945 | ||||
| Bumper | 9 December 1944 | Transferred to Turkey as Çanakkale 16 November 1950; decommissioned 11 August 1976 | ||||
| Burrfish | 13 September 1943 | Transferred to Canada as Grilse 11 May 1961; sunk as target 19 November 1969 | ||||
| CA 1 | Regia Marina | CA (Series I) | midget submarine | 16.1 | 15 April 1938 | Scuttled 9 September 1943 |
| CA 2 | late April 1938 | Captured by Germany 9 September 1943; Scuttled August 1944 | ||||
| CA 3 | CA (Series II) | midget submarine | January 1943 | Scuttled 9 September 1943 | ||
| CA 4 | January 1943 | Scuttled 9 September 1943 | ||||
| Cabezon | United States Navy | Balao | fleet submarine | 2,391 | 30 December 1944 | Sold for scrap 28 December 1971 |
| Cabrilla | 24 May 1943 | Museum ship 19 October 1968; sold for scrap 18 April 1972 | ||||
| Cachalot | Cachalot | submarine | 1,650 | 1 December 1933 | Sold for scrap 26 January 1947 | |
| Cachalot | Royal Navy | Grampus | minelayer submarine | 2,157 | 15 August 1938 | Sunk 30 July 1941 |
| Caïman | French Navy | Requin | submarine | 1,132 | 7 February 1928 | Scuttled 27 November 1942; refloated February 1943; sunk 11 March 1944 |
| Caiman | United States Navy | Balao | fleet submarine | 2,391 | 17 July 1944 | Transferred to Turkey as Dumlupınar 30 June 1972; retired 15 September 1986 |
| Calypso | French Navy | Circé | submarine | 764 | 29 January 1927 | Disarmed December 1940; captured by Italy 8 December 1942; renamed FR117; scuttled 6 May 1943; refloated; stricken 18 August 1947 |
| Capelin | United States Navy | Balao | fleet submarine | 2,391 | 4 June 1943 | Missing after 2 December 1943 |
| Capitaine | 26 January 1945 | Transferred to Italy 5 March 1966; retired 5 December 1977 | ||||
| Carbonero | 7 February 1945 | Sunk as target 27 April 1975 | ||||
| Carp | 28 February 1945 | Sold for scrap 26 July 1973 | ||||
| Casabianca | French Navy | Redoutable | cruiser submarine | 1,968 | 1 January 1937 | Scrapped February 1952 |
| Catfish | United States Navy | Balao | fleet submarine | 2,391 | 19 March 1945 | Transferred to Argentina as Santa Fe 1 July 1971; scuttled 20 February 1985 |
| Cavalla | Gato | fleet submarine | 2,424 | 29 February 1944 | Museum ship 21 January 1971 | |
| CB-1 | Regia Marina | CB | midget submarine | 44.3 | 27 January 1941 | Transferred to Romania September 1943; Scuttled 25 August 1944; refloated by Soviet Union; commissioned in Soviet Navy as TM-4; scrapped 1945 |
| CB-2 | 27 January 1941 | Transferred to Romania September 1943; Scuttled August 1944; refloated by Soviet Union; commissioned in Soviet Navy as TM-5; scrapped 1945 | ||||
| CB-3 | 10 May 1941 | Transferred to Romania September 1943; Scuttled 25 August 1944; refloated by Soviet Union; commissioned in Soviet Navy as TM-6; scrapped 1945 | ||||
| CB-4 | 10 May 1941 | Transferred to Romania September 1943; Scuttled August 1944; refloated by Soviet Union; commissioned in Soviet Navy as TM-7; scrapped 1945 | ||||
| CB-5 | 10 May 1941 | Sunk 13 June 1942 | ||||
| CB-6 | 10 May 1941 | Transferred to Romania September 1943; Scuttled August 1944 | ||||
| CB-7 | 1 August 1943 | Captured by Germany 9 September 1943; cannibalized for spare parts | ||||
| CB-8 | 1 August 1943 | Scrapped 1948 | ||||
| CB-9 | 1 August 1943 | Scrapped 1948 | ||||
| CB-10 | 1 August 1943 | Scrapped 1948 | ||||
| CB-11 | 24 August 1943 | Scrapped 1948 | ||||
| CB-12 | 24 August 1943 | Scrapped 1948 | ||||
| CB-13 |  National Republican Navy | CB | midget submarine | 44.3 | late 1943 | Sunk 23 March 1945 |
| CB-14 | late 1943 | Sunk, possibly on 23 March 1945 | ||||
| CB-15 | late 1943 | Destroyed in port 20 April 1944 | ||||
| CB-16 | late 1943 | Beached after crew mutinied 2 October 1944; surrendered to United Kingdom | ||||
| CB-17 | late 1943 | Sunk 3 April 1945 | ||||
| CB-18 | late 1943 | Sunk 31 March 1945 | ||||
| CB-19 | late 1943 | Captured by the Yugoslav Partisans May 1945; scrapped 1947 | ||||
| CB-20 | late 1943 | Captured by the Yugoslav Partisans May 1945; in service in Yugoslav Navy as Mališan during 1950s; museum ship 1959 | ||||
| CB-21 | late 1943 | Sunk in collision 29 April 1945 | ||||
| CB-22 | late 1943 | Sunk 11 March 1945 | ||||
| Cérès | French Navy | Minerve | submarine | 856 | 15 July 1939 | Scuttled 9 November 1942, salvaged 1943, stricken 18 February 1946 |
| Cero | United States Navy | Gato | fleet submarine | 2,424 | 4 July 1943 | Sold for scrap October 1970 |
| Charr | Balao | fleet submarine | 2,391 | 23 September 1944 | Sold for scrap 17 August 1972 | |
| Chivo | 28 April 1945 | Transferred to Argentina as Santiago del Estero 1 July 1971; sold for scrap 1983 | ||||
| Chopper | 25 May 1945 | Sank 21 July 1976 | ||||
| Chub | 21 October 1944 | Transferred to Turkey as Gür 25 May 1948; decommissioned 12 December 1975; scrapped | ||||
| Circé | French Navy | Circé | submarine | 764 | 12 May 1928 | Disarmed December 1940; captured by Italy 8 December 1942; sunk 31 January 1943 |
| Ciro Menotti | Regia Marina | Bandiera | submarine | 1,080 | 29 July 1930 | Stricken 1 February 1948 |
| Cisco | United States Navy | Balao | fleet submarine | 2,391 | 10 May 1943 | Sunk 28 September 1943 |
| Clamagore | 28 June 1945 | Museum ship May 1981 | ||||
| Clyde | Royal Navy | River | submarine | 2,723 | 12 April 1935 | Paid off 30 July 1946 |
| Cobbler | United States Navy | Balao | fleet submarine | 2,391 | 8 August 1945 | Transferred to Turkey as Çanakkale 21 November 1973; decommissioned 22 January 1998 |
| Cobia | Gato | fleet submarine | 2,424 | 29 March 1944 | Memorial ship 17 August 1970 | |
| Cobalto | Regia Marina | Acciaio | coastal submarine | 864 | 18 March 1942 | Sunk 12 August 1942 |
| Cochino | United States Navy | Balao | fleet submarine | 2,424 | 25 August 1945 | Sank 26 August 1949 |
| Cod | Gato | fleet submarine | 2,424 | 21 June 1943 | Museum ship 1 May 1976 | |
| Comandante Cappellini | Regia Marina | Marcello | submarine | 1,313 | 23 September 1939 | Seized by Japan and transferred to Germany as UIT-24 10 September 1943; seized by Japan 5 May 1945; commissioned as I-503 May 1945; surrendered to United States August 1945; scuttled 16 April 1946 |
| Comandante Faà di Bruno | 23 October 1939 | Missing after 31 October 1940 | ||||
| Conger | United States Navy | Tench | fleet submarine | 2,414 | 14 February 1945 | Sold for scrap 9 July 1964 |
| Console Generale Liuzzi | Regia Marina | Liuzzi | submarine | 1,484 | 21 November 1939 | Sunk 27 June 1940 |
| Corallo | Perla | coastal submarine | 846 | 26 September 1936 | Sunk 13 December 1942 | |
| Corvina | United States Navy | Gato | fleet submarine | 2,424 | 6 August 1943 | Sunk 16 November 1943 |
| Crevalle | Balao | fleet submarine | 2,391 | 21 April 1944 | Sold for scrap 17 March 1971 | |
| Croaker | Gato | fleet submarine | 2,424 | 24 June 1943 | Museum ship 27 June 1976 | |
| Cutlass | Tench | fleet submarine | 2,414 | 17 March 1945 | Transferred to Republic of China as Hai Shih 15 April 1973 | |
| Curie | Royal Navy Free French Naval Forces | U | submarine | 740 | 2 May 1943 | Formerly HMS Vox; loaned to Free French Naval Forces 2 May 1943; returned to United Kingdom July 1946; scrapped May 1949 |
| Cuttlefish | United States Navy | Cachalot | submarine | 1,650 | 8 June 1934 | Sold for scrap 12 February 1947 |
| Dace | Gato | fleet submarine | 2,424 | 23 July 1943 | Transferred to Italy as Leonardo da Vinci 31 January 1955; sold for scrap 1 April 1975 | |
| Dagabur | Regia Marina | Adua | coastal submarine | 843 | 9 April 1937 | Sunk 12 August 1942 |
| Danaé | French Navy | Ariane | submarine | 787 | Scuttled 9 November 1942 | |
| Dandolo | Regia Marina | Marcello | submarine | 1,313 | 25 March 1938 | Stricken 1 February 1948 |
| Darter | United States Navy | Gato | fleet submarine | 2,424 | 7 September 1943 | Wrecked 24 October 1944 |
| Dauphin | French Navy | Requin | submarine | 1,132 | 22 November 1927 | Captured by Italy 8 December 1942; renamed FR 115; captured by Germany 9 September 1943; scuttled 15 September 1943 |
| Dekabrist |  Soviet Navy | Dekabrist | submarine | 1,354 | 3 November 1928 | Lost in training accident 13 November 1940 |
| Delfin |  Royal Hellenic Navy | V | submarine | 740 | 16 October 1944 | Formerly HMS Vengeful; loaned to Greece April 1945; returned to United Kingdom 1957; scrapped March 1958 |
| Delfino | Regia Marina | Squalo | submarine | 1,107 | 19 June 1931 | Sunk in collision 23 March 1943 |
| Delfinul |  Royal Romanian Navy | submarine | 900 | 1936 | Captured by Soviet Union August 1944; returned 1951; scrapped 1957 | |
| Dentuda | United States Navy | Balao | fleet submarine | 2,391 | 30 December 1944 | Sold for scrap 12 February 1969 |
| Des Geneys | Regia Marina | Pisani | submarine | 1,040 | 31 October 1929 | Decommissioned 16 April 1942; scrapped |
| Dessiè | Adua | coastal submarine | 843 | 14 April 1937 | Sunk 28 November 1942 | |
| Devilfish | United States Navy | Balao | fleet submarine | 2,391 | 1 September 1944 | Sunk as a target 14 August 1968 |
| Diablo | Tench | fleet submarine | 2,414 | 31 March 1945 | Transferred to Pakistan as Ghazi 1 June 1964; lost 4–5 December 1971 | |
| Diamant | French Navy | Saphir | minelayer submarine | 925 | 21 June 1934 | Scuttled 27 November 1942; refloated 29 March 1943; sunk 22 June 1944 |
| Diamante | Regia Marina | Sirena | coastal submarine | 837 | 18 November 1933 | Sunk 20 June 1940 |
| Diane | French Navy | Diane | submarine | 796 | 1 September 1932 | Scuttled 9 November 1942 |
| Diaspro | Regia Marina | Perla | coastal submarine | 846 | 22 August 1936 | Stricken 1 February 1948 |
| Dolfijn |  Royal Netherlands Navy | U | submarine | 730 | 8 October 1942 | Scrapped 1952 |
| Dolphin | United States Navy | V-7 | submarine | 2,240 | 1 June 1932 | Sold for scrap 26 August 1946 |
| Domenico Millelire | Regia Marina | Balilla | cruiser submarine | 1,874 | 11 August 1928 | Decommissioned 1 April 1943, purchased by Pirelli and transformed into latex storage 1948, scrapped 1977 |
| Dorado | United States Navy | Gato | fleet submarine | 2,424 | 28 August 1943 | Sunk 12 October 1943 |
| Doris (Q135) | French Navy | Circé | submarine | 764 | 26 May 1928 | Sunk 8 May 1940 |
| Doris (P84) | Free French Naval Forces | V | submarine | 740 | 1 August 1944 | Formerly HMS Vineyard; returned to the United Kingdom 18 November 1947; scrapped June 1950 |
| Dragonet | United States Navy | Balao | fleet submarine | 2,391 | 6 March 1944 | Scuttled 17 September 1961 |
| Drum | Gato | fleet submarine | 2,424 | 1 November 1941 | Museum ship 14 April 1969 | |
| Durbo | Regia Marina | Adua | coastal submarine | 843 | 1 July 1938 | Scuttled 18 October 1940 |
| Dzik |  Polish Navy | U | submarine | 730 | 16 December 1942 | Transferred to Denmark as U 1 July 1947; scrapped 1958 |
| Emo | Regia Marina | Marcello | submarine | 1,313 | 25 October 1938 | Scuttled 10 November 1942 |
| Enrico Tazzoli | Calvi | cruiser submarine | 2,028 | 18 May 1936 | Missing after 17 May 1943 | |
| Enrico Toti | Balilla | cruiser submarine | 1,874 | 19 September 1928 | Decommissioned 1 April 1943, converted into blockship, scrapped 1946 | |
| Entemedor | United States Navy | Balao | fleet submarine | 2,391 | 6 April 1945 | Transferred to Turkey as Preveze on 31 July 1972; discarded 1987 |
| Escolar | fleet submarine | 2,391 | 2 June 1944 | Missing after 17 October 1944 | ||
| Espadon | French Navy | Requin | submarine | 1,132 | 16 December 1927 | Captured by Italy 8 December 1942; renamed FR 114; scuttled 15 September 1943; refloated; not repaired |
| Ettore Fieramosca | Regia Marina | Balilla | cruiser submarine | 2,094 | 1930 | Decommissioned April 1941 |
| Eurydice | French Navy | Ariane | submarine | 787 | 1 September 1929 | Scuttled 27 November 1942 |
| Filippo Corridoni | Regia Marina | Bragadin | submarine | 981 | 17 November 1931 | Stricken 1 February 1948 |
| Finback | United States Navy | Gato | fleet submarine | 2,424 | 31 January 1942 | Sold for scrap 15 July 1959 |
| Fisalia | Regia Marina | Argonauta | coastal submarine | 1,080 | 5 June 1932 | Sunk 28 September 1941 |
| Flasher | United States Navy | Gato | fleet submarine | 2,424 | 25 September 1943 | Sold for scrap 8 June 1963 |
| Flier | 18 October 1943 | Sunk 13 August 1944 | ||||
| Flounder | 29 November 1943 | Scrapped February 1960 | ||||
| Flutto | Regia Marina | Flutto | submarine | 1,093 | 20 March 1943 | Sunk 11 July 1943 |
| Flying Fish | United States Navy | Gato | fleet submarine | 2,424 | 10 December 1941 | Sold for scrap 1 May 1959 |
| Foca | Regia Marina | Foca | minelayer submarine | 1,625 | 6 November 1937 | Sunk 13 October 1940 |
| FR 111 | Requin | submarine | 1,132 | 7 May 1928 | Former French submarine Phoque; captured 8 December 1942; sunk 28 February 1943 | |
| FR 112 | Saphir | minelayer submarine | 925 | 30 September 1930 | Former French submarine Saphir; captured 8 December 1942; captured bv Germany and scuttled 15 September 1943 | |
| FR 113 | Requin | submarine | 1,132 | 28 May 1926 | Former French submarine Requin; captured 8 December 1942; captured by Germany 9 September 1943; sold for scrap 1944 | |
| FR 114 | 16 December 1927 | Former French submarine Espadon; captured 8 December 1942; scuttled 15 September 1943; refloated; not repaired | ||||
| FR 115 | 22 November 1927 | Former French submarine Dauphin; captured 8 December 1942; captured by Germany 9 September 1943; scuttled 15 September 1943 | ||||
| FR 116 | Saphir | minelayer submarine | 925 | 10 September 1930 | Former French submarine Turquoise; captured 8 December 1942; captured bv Germany and scuttled 8 September 1943 | |
| FR 117 | Circé | submarine | 764 | 29 January 1927 | Former French submarine Calypso; captured 8 December 1942; scuttled 6 May 1943; refloated; stricken 18 August 1947 | |
| Fratelli Bandiera | Bandiera | submarine | 1,080 | 2 June 1930 | Stricken 1 February 1948 | |
| Fresia |  Chilean Navy | H | submarine | 434 | 1917 | Scrapped 1945 |
| Fresnel | French Navy | Redoutable | cruiser submarine | 1,968 | 22 February 1932 | Scuttled 27 November 1942; refloated 28 January 1943; sunk 11 March 1944 |
| Gabilan | United States Navy | Gato | fleet submarine | 2,424 | 28 December 1943 | Sold for scrap 11 January 1960 |
| Galatea | Regia Marina | Sirena | coastal submarine | 837 | 25 June 1934 | Stricken 1 February 1948 |
| Galatée | French Navy | Sirène | submarine | 745 | 1927 | Scuttled 27 November 1942 |
| Galileo Galilei | Regia Marina Royal Navy | Archimede | submarine | 1,239 | 19 March 1934 | Captured by United Kingdom 18 June 1940, commissioned as HMS X2 June 1942, paid off January 1946 |
| Galileo Ferraris | Regia Marina | 31 January 1935 | Sunk 25 October 1941 | |||
| Galvani | Brin | submarine | 1,380 | 29 July 1938 | Sunk 26 June 1940 | |
| Gar | United States Navy | Tambor | fleet submarine | 2,370 | 14 April 1941 | Sold for scrap 11 December 1959 |
| Gato | Gato | fleet submarine | 2,424 | 31 December 1941 | Sold for scrap 25 July 1960 | |
| Gemma | Regia Marina | Perla | coastal submarine | 846 | 8 July 1936 | Sunk 8 October 1940 |
| General Mola |  Spanish Navy | Archimede | submarine | 1,239 | 1935 | Stricken 1959 |
| General Sanjurjo | 1934 | Stricken 1959 | ||||
| Giada | Regia Marina | Acciaio | coastal submarine | 864 | 6 December 1941 | Stricken 1 January 1966 |
| Giovanni Bausan | Pisani | submarine | 1,040 | 15 September 1929 | Decommissioned 16 April 1942; scrapped | |
| Giovanni da Procida | Mameli | submarine | 993 | 20 January 1929 | Decommissioned 16 April 1942; scrapped | |
| Giuseppe Finzi | Calvi | cruiser submarine | 2,028 | 8 January 1936 | Captured by Germany 9 September 1943; renamed UIT-21; scuttled 25 August 1944 | |
| Glauco | Glauco | submarine | 1,305 | January 1936 | Scuttled 27 June 1941 | |
| Goffredo Mameli | Mameli | submarine | 993 | 20 January 1929 | Stricken 1 February 1948 | |
| Golet | United States Navy | Gato | fleet submarine | 2,424 | 30 November 1943 | Sunk 14 June 1944 |
| Gondar | Regia Marina | Adua | coastal submarine | 843 | 28 February 1938 | Scuttled 30 September 1940 |
| Gorgo | Flutto | submarine | 1,093 | 11 November 1942 | Sunk 21 May 1943 | |
| Grampus | Royal Navy | Grampus | submarine | 2,157 | 10 March 1937 | Sunk 16 June 1940 |
| Grampus | United States Navy | Tambor | fleet submarine | 2,370 | 23 May 1941 | Sunk 5 March 1943 |
| Granito | Regia Marina | Acciaio | coastal submarine | 864 | 3 January 1942 | Sunk 9 November 1942 |
| Graph | Royal Navy | Type VIIC | submarine | 857 | 15 May 1941 | Former German U-570, captured by United Kingdom 27 August 1941, wrecked September 1944 |
| Grayback | United States Navy | Tambor | fleet submarine | 2,370 | 30 June 1941 | Sunk 27 February 1944 |
| Grayling | 1 March 1941 | Sunk between 9 and 12 September 1943 | ||||
| Greenling | Gato | fleet submarine | 2,424 | 21 January 1942 | Sold for scrap 21 June 1960 | |
| Grenadier | Tambor | fleet submarine | 2,370 | 1 May 1941 | Scuttled 22 April 1943 | |
| Grouper | Gato | fleet submarine | 2,424 | 12 February 1942 | Sold for scrap 11 August 1970 | |
| Growler | 20 March 1942 | Sunk 8 November 1944 | ||||
| Grunion | 11 April 1942 | Sunk ca. 30 July 1942 | ||||
| Guacolda | Chilean Navy | H | submarine | 434 | 1917 | Scrapped 1949 |
| Guale | 1917 | Scrapped 1945 | ||||
| Guardfish | United States Navy | Gato | fleet submarine | 2,424 | 8 May 1942 | Sunk as target 10 October 1961 |
| Guavina | 23 December 1943 | Sunk as target 14 November 1967 | ||||
| Guglielmo Marconi | Regia Marina | Marconi | submarine | 1,490 | 2 February 1940 | Missing after 28 October 1941 |
| Guglielmotti | Brin | submarine | 1,380 | 12 October 1938 | Sunk 17 March 1942 | |
| Guitarro | United States Navy | Gato | fleet submarine | 2,424 | 26 January 1944 | Sold for scrap December 1959 |
| Gunnel | 20 August 1942 | Transferred to Turkey as Preveze 7 August 1954; scrapped September 1983 | ||||
| Gür |  Turkish Navy | submarine | 968 | 29 December 1936 | Decommissioned 1947 | |
| Gurnard | United States Navy | Gato | fleet submarine | 2,424 | 18 September 1942 | Sold for scrap 29 October 1961 |
| H1 | Regia Marina | H | submarine | 520 | 23 December 1916 | Stricken 23 March 1947 |
| H2 | 15 December 1916 | Stricken 23 March 1947 | ||||
| H4 | 15 May 1917 | Stricken 23 March 1947 | ||||
| H6 | 23 July 1917 | Scuttled 1 September 1943 | ||||
| H8 | 27 June 1918 | Sunk 5 June 1943 | ||||
| H28 | Royal Navy | H | submarine | 510 | 29 June 1918 | Scrapped 18 August 1944 |
| H31 | 21 February 1919 | Sunk 24 December 1941 | ||||
| H32 | 14 May 1919 | Scrapped 18 October 1944 | ||||
| H33 | 17 May 1919 | Scrapped 19 May 1944 | ||||
| H34 | 10 September 1919 | Scrapped July 1945 | ||||
| H43 | 25 November 1919 | Scrapped November 1944 | ||||
| H44 | 15 April 1920 | Scrapped February 1945 | ||||
| H49 | 25 October 1919 | Sunk 18 October 1940 | ||||
| H50 | 3 February 1920 | Scrapped July 1945 | ||||
| Ha-101 |  Imperial Japanese Navy | Ha-101 | transport submarine | 493 | 22 November 1944 | Scrapped or scuttled October 1945 |
| Ha-102 | 6 December 1944 | Scrapped or scuttled October 1945 | ||||
| Ha-103 | 3 February 1945 | Scuttled 1 April 1946 | ||||
| Ha-104 | 1 December 1944 | Scuttled October 1945 | ||||
| Ha-105 | 19 February 1945 | Scuttled 1 April 1946 | ||||
| Ha-106 | 15 December 1944 | Scuttled 1 April 1946 | ||||
| Ha-107 | 7 February 1945 | Scuttled 1 April 1946 | ||||
| Ha-108 | 6 May 1945 | Scuttled 1 April 1946 | ||||
| Ha-109 | 10 March 1945 | Scuttled 1 April 1946 | ||||
| Ha-111 | 13 July 1945 | Scuttled 1 April 1946 | ||||
| Ha-201 | Ha-201 | submarine | 440 | 31 May 1945 | Scuttled 1 April 1946 | |
| Ha-202 | 31 May 1945 | Scuttled 1 April 1946 | ||||
| Ha-203 | 20 June 1945 | Scuttled 1 April 1946 | ||||
| Ha-204 | 25 June 1945 | Wrecked 29 October 1945 | ||||
| Ha-205 | 3 July 1945 | Scuttled 9 May 1946 | ||||
| Ha-207 | 14 August 1945 | Scuttled 5 April 1946 | ||||
| Ha-208 | 4 August 1945 | Scuttled 1 April 1946 | ||||
| Ha-209 | 4 August 1945 | Wrecked 18 August 1945 | ||||
| Ha-210 | 11 August 1945 | Scuttled 5 April 1946 | ||||
| Ha-216 | 16 August 1945 | Scuttled 5 April 1946 | ||||
| Hackleback | United States Navy | Balao | fleet submarine | 2,391 | 7 November 1944 | Sold for scrap 4 December 1968 |
| Haddo | Gato | fleet submarine | 2,424 | 9 October 1942 | Sold for scrap 4 May 1959 | |
| Haddock | 14 March 1942 | Sold for scrap 23 August 1960 | ||||
| Hake | 30 October 1942 | Sold for scrap 5 December 1972 | ||||
| Halibut | 10 April 1942 | Sold for scrap 9 December 1946 | ||||
| Hammerhead | 1 March 1944 | Transferred to Turkey as Cerbe 23 October 1954; decommissioned 4 May 1972; scrapped | ||||
| Harder | 2 December 1942 | Sunk 24 August 1944 | ||||
| Hardhead | Balao | fleet submarine | 2,391 | 18 April 1944 | Transferred to Greece as Papanikolis 26 July 1972; sold for scrap 1993 | |
| Hawkbill | 17 May 1944 | Transferred to the Netherlands as Zeeleeuw 21 April 1953; sold for scrap, 24 November 1970 | ||||
| Henri Poincaré | French Navy | Redoutable | cruiser submarine | 1,968 | 23 December 1931 | Scuttled 27 November 1942; refloated; scrapped September 1943 |
| Herring | United States Navy | Gato | fleet submarine | 2,424 | 4 May 1942 | Sunk 1 June 1944 |
| Hoe | 16 December 1942 | Sold for scrap 10 September 1960 | ||||
| Hrabri |  Royal Yugoslav Navy Regia Marina | Hrabri | submarine | 1,164 | 1927 | Captured and scrapped by the Italians in 1941 |
| Humaytá |  Brazilian Navy | Balilla (Modified) | cruiser submarine | 1,884 | 20 July 1929 | Decommissioned 25 November 1950 |
| I-1 | Imperial Japanese Navy | Type J1 | cruiser submarine | 2,791 | 10 March 1926 | Wrecked 29 January 1943 |
| I-2 | 24 July 1926 | Sunk 7 April 1944 | ||||
| I-3 | 30 November 1926 | Sunk 9 December 1942 | ||||
| I-4 | 24 December 1929 | Sunk 21 December 1942 | ||||
| I-5 | Type J1 Modified | submarine aircraft carrier | 2,921 | 31 July 1932 | Sunk 19 July 1944 | |
| I-6 | Type J2 | submarine aircraft carrier | 2,921 | 15 May 1935 | Sunk 16 June 1944 | |
| I-7 | Type J3 | submarine aircraft carrier | 3,583 | 31 March 1937 | Wrecked 22 June 1943 | |
| I-8 | 5 December 1938 | Sunk 31 March 1945 | ||||
| I-9 | Type A1 | submarine aircraft carrier | 4,129 | 13 February 1941 | Sunk 13 June 1943 | |
| I-10 | 31 October 1941 | Sunk 4 July 1944 | ||||
| I-11 | 16 May 1942 | Missing after 11 January 1944 | ||||
| I-12 | Type A2 | submarine | 4,150 | 25 May 1944 | Sunk 13 November 1944 | |
| I-13 | Type A3 | submarine aircraft carrier | 4,762 | 16 December 1944 | Sunk 16 July 1945 | |
| I-14 | 14 March 1945 | Sunk as target 28 May 1946 | ||||
| I-15 | Type B1 | submarine aircraft carrier | 3,654 | 30 September 1940 | Sunk 10 November 1942 | |
| I-16 | Type C1 | midget submarine-carrying submarine | 3,561 | 30 March 1940 | Sunk 19 May 1944 | |
| I-17 | Type B1 | submarine aircraft carrier | 3,654 | 24 January 1941 | Sunk 19 August 1943 | |
| I-18 | Type C1 | midget submarine-carrying submarine | 3,561 | 31 January 1941 | Sunk 11 February 1943 | |
| I-19 | Type B1 | submarine aircraft carrier | 3,654 | 28 April 1941 | Sunk 25 November 1943 | |
| I-20 | Type C1 | midget submarine-carrying submarine | 3,561 | 26 September 1940 | Missing after 31 August 1943 | |
| I-21 | Type B1 | submarine aircraft carrier | 3,654 | 15 July 1941 | Sunk 29 November 1943 | |
| I-22 | Type C1 | midget submarine-carrying submarine | 3,561 | 10 March 1941 | Sunk 6 October 1942 | |
| I-23 | Type B1 | submarine aircraft carrier | 3,654 | 27 September 1941 | Missing after 24 February 1942 | |
| I-24 | Type C1 | midget submarine-carrying submarine | 3,561 | 31 October 1941 | Sunk 1 June 1943 | |
| I-25 | Type B1 | submarine aircraft carrier | 3,654 | 15 October 1941 | Sunk 3 September 1943 | |
| I-26 | 6 November 1941 | Sunk 26 October 1944 | ||||
| I-27 | 24 February 1942 | Sunk 12 February 1944 | ||||
| I-28 | 6 February 1942 | Sunk 17 May 1942 | ||||
| I-29 | 27 February 1942 | Sunk 26 July 1944 | ||||
| I-30 | 28 February 1942 | Sunk 13 October 1942 | ||||
| I-31 | 30 May 1942 | Sunk 13 May 1943 | ||||
| I-32 | 26 April 1942 | Sunk 24 March 1944 | ||||
| I-33 | 26 April 1942 | Sank in diving accident 13 June 1944 | ||||
| I-34 | 31 August 1942 | Sunk 13 November 1943 | ||||
| I-35 | 31 August 1942 | Sunk 23 November 1943 | ||||
| I-36 | 30 September 1942 | Scuttled 1 April 1946 | ||||
| I-37 | 10 March 1943 | Sunk 19 November 1944 | ||||
| I-38 | 31 January 1943 | Sunk 13 November 1944 | ||||
| I-39 | 22 April 1943 | Missing after 25 November 1943 | ||||
| I-40 | Type B2 | submarine | 3,700 | 31 July 1943 | Missing after 22 November 1943 | |
| I-41 | 18 September 1943 | Sunk 18 November 1944 | ||||
| I-42 | 3 November 1943 | Sunk 23 March 1944 | ||||
| I-43 | 5 November 1943 | Sunk 15 February 1944 | ||||
| I-44 | 31 January 1944 | Missing April 1945 | ||||
| I-45 | 28 December 1943 | Sunk 29 October 1944 | ||||
| I-46 | Type C2 | submarine | 3,621 | 29 February 1944 | Missing October 1944 | |
| I-47 | 10 July 1944 | Scuttled 1 April 1946 | ||||
| I-48 | 5 September 1944 | Sunk 23 January 1945 | ||||
| I-52 | Type C3 | transport submarine | 3,644 | 28 December 1943 | Sunk 24 June 1944 | |
| I-53 | submarine | 3,644 | 20 February 1944 | Scuttled 1 April 1946 | ||
| I-54 | Type B3 | submarine aircraft carrier | 3,747 | 31 March 1944 | Missing after 23 October 1944 | |
| I-55 | Type C3 | transport submarine | 3,644 | 20 April 1944 | Missing after 13 July 1944 | |
| I-56 | Type B3 | submarine aircraft carrier | 3,747 | 8 June 1944 | Missing April 1945 | |
| I-58 | 7 September 1944 | Scuttled 1 April 1946 | ||||
| I-60 | KD3 type | cruiser submarine | 2,300 | 24 December 1929 | Sunk 17 January 1942 | |
| I-64 | KD4 type | cruiser submarine | 2,300 | 30 August 1930 | Sunk 17 May 1942 | |
| I-70 | KD6 type | cruiser submarine | 2,440 | 9 November 1935 | Sunk 10 December 1941 | |
| I-73 | 7 January 1937 | Sunk 27 January 1942 | ||||
| I-121 (ex-I-21) | Kiraisen type | minelayer submarine | 1,768 | 31 March 1927 | Scuttled 30 April 1946 | |
| I-122 (ex-I-22) | 28 October 1928 | Sunk 10 June 1945 | ||||
| I-123 (ex-I-23) | 28 April 1928 | Sunk 29 August 1942 | ||||
| I-124 (ex-I-24) | 10 December 1928 | Sunk 20 January 1942 | ||||
| I-152 (ex-I-52) | KD2 type | training submarine | 2,500 | 1 November 1924 | Scrapped 1946–1948 | |
| I-153 (ex-I-53) | KD3A type | submarine | 2,300 | 30 March 1927 | Scuttled May 1946 | |
| I-154 (ex-I-54) | 15 December 1927 | Scuttled May 1946 | ||||
| I-155 (ex-I-55) | 5 September 1927 | Scuttled 8 May 1946 | ||||
| I-156 (ex-I-56) | KD3B type | submarine | 2,300 | 31 March 1929 | Scuttled 1 April 1946 | |
| I-157 (ex-I-57) | 15 May 1928 | Scuttled 1 April 1946 | ||||
| I-158 (ex-I-58) | KD3A type | submarine | 2,300 | 24 December 1929 | Scuttled 1 April 1946 | |
| I-159 (ex-I-59) | KD3B type | submarine | 2,300 | 31 March 1930 | Scuttled 1 April 1946 | |
| I-162 (ex-I-62) | KD4 type | submarine | 2,300 | 24 April 1930 | Scuttled 1 April 1946 | |
| I-165 (ex-I-65) | KD5 type | submarine | 2,330 | 1 December 1932 | Sunk 27 June 1945 | |
| I-166 (ex-I-66) | 10 November 1932 | Sunk 17 July 1944 | ||||
| I-168 (ex-I-68) | KD6 type | cruiser submarine | 2,440 | 31 July 1934 | Sunk 27 July 1943 | |
| I-169 (ex-I-69) | 28 September 1935 | Sank in diving accident 4 April 1944 | ||||
| I-171 (ex-I-71) | 24 December 1935 | Sunk 1 February 1944 | ||||
| I-172 (ex-I-72) | 7 January 1937 | Sunk October–November 1942 | ||||
| I-174 (ex-I-74) | 15 August 1938 | Sunk 12 April 1944 | ||||
| I-175 (ex-I-75) | 8 December 1938 | Sunk 4 February 1944 | ||||
| I-176 | KD7 type | cruiser submarine | 2,602 | 4 August 1942 | Sunk 16 May 1944 | |
| I-177 | 28 December 1942 | Sunk 3 October 1944 | ||||
| I-178 | 26 December 1942 | Missing June 1943 | ||||
| I-179 | 18 June 1943 | Sank 14 July 1944 | ||||
| I-180 | 15 January 1943 | Sunk 27 April 1944 | ||||
| I-181 | 24 May 1943 | Wrecked 16 January 1944 | ||||
| I-182 | 10 May 1943 | Sunk 1 September 1944 | ||||
| I-183 | 3 October 1943 | Sunk 29 April 1944 | ||||
| I-184 | 15 October 1943 | Sunk 19 June 1944 | ||||
| I-185 | 23 September 1943 | Sunk 22 June 1944 | ||||
| I-201 | Sentaka type | submarine | 1,479 | 2 February 1945 | Sunk as target 23 May 1946 | |
| I-202 | 12 February 1945 | Scuttled 5 April 1946 | ||||
| I-203 | 29 May 1945 | Sunk as target 21 May 1946 | ||||
| I-351 | Senho type | submarine tanker | 4,290 | 28 January 1945 | Sunk 14 July 1945 | |
| I-361 | Type D1 | transport submarine/kaiten carrier | 2,215 | 25 May 1944 | Sunk 31 May 1945 | |
| I-362 | transport submarine | 23 May 1944 | Sunk 14 January 1945 | |||
| I-363 | transport submarine/kaiten carrier | 8 July 1944 | Sunk 29 October 1945 | |||
| I-364 | transport submarine | 14 June 1944 | Sunk 16 September 1944 | |||
| I-365 | transport submarine | 1 August 1944 | Sunk 29 November 1944 | |||
| I-366 | transport submarine/kaiten carrier | 15 August 1944 | Scuttled 1 April 1946 | |||
| I-367 | transport submarine/kaiten carrier | 3 August 1944 | Scuttled 1 April 1946 | |||
| I-368 | transport submarine/kaiten carrier | 25 August 1944 | Sunk 26 February 1945 | |||
| I-369 | transport submarine | 9 October 1944 | Scrapped 1946 | |||
| I-370 | transport submarine/kaiten carrier | 4 September 1944 | Sunk 26 February 1945 | |||
| I-371 | transport submarine | 2 October 1944 | Missing February 1945 | |||
| I-372 | transport submarine | 8 November 1944 | Sunk 18 July 1945 | |||
| I-373 | Type D2 | transport/tanker submarine | 2,240 | 14 April 1945 | Sunk 14 August 1945 | |
| I-400 | Sentoku type | submarine aircraft carrier | 6,560 | 30 December 1944 | Sunk as target 4 June 1946 | |
| I-401 | submarine aircraft carrier | 8 January 1945 | Sunk as target 31 May 1946 | |||
| I-402 | submarine tanker | 24 July 1945 | Scuttled 1 April 1946 | |||
| I-501 (ex-U-181) | Type IXD2 | submarine | 1,771 | 16 July 1945 | Scuttled 12 February 1946 | |
| I-502 (ex-U-862) | 15 July 1945 | Scuttled 13 February 1946 | ||||
| I-503 | Marcello | submarine | 1,313 | 10 May 1945 | Former Italian submarine Comandante Cappellini and German UIT-24; scuttled 16 April 1946 | |
| I-504 | Marconi | submarine | 1,400 | 10 May 1945 | Former Italian submarine Luigi Torelli and German UIT-25; scuttled 16 April 1946 | |
| I-505 (ex-U-219) | Type XB | minelayer submarine | 2,143 | 15 July 1945 | Scuttled 3 February 1946 | |
| I-506 (ex-U-195) | Type IXD1 | submarine | 1,771 | 15 July 1945 | Scuttled 15 February 1946 | |
| Icefish | United States Navy | Balao | fleet submarine | 2,391 | 10 June 1944 | Transferred to the Netherlands as Walrus 21 February 1953; sold for scrap 15 August 1971 |
| Iku-Turso |  Finnish Navy | Vetehinen | submarine | 705 | 13 October 1931 | Decommissioned 1946, scrapped 1950s |
| Irex | United States Navy | Tench | fleet submarine | 2,414 | 14 May 1945 | Sold for scrap 13 September 1971 |
| Iride | Regia Marina | Perla | coastal submarine | 839 | 6 November 1936 | Sunk 22 August 1940 |
| Iris | French Navy | Minerve | submarine | 856 | 15 September 1936 | Decommissioned 1 February 1950 |
| Jack | United States Navy | Gato | fleet submarine | 2,424 | 6 January 1943 | Transferred to Greece as Amfitriti 21 April 1958; sunk as target 5 September 1967 |
| Jalea | Regia Marina | Argonauta | coastal submarine | 1,080 | 16 March 1933 | Stricken 1 February 1948 |
| Jallao | United States Navy | Balao | fleet submarine | 2,391 | 8 July 1944 | Transferred to Spain as Narciso Monturiol 26 June 1974; scuttled 1985 |
| Jantina | Regia Marina | Argonauta | coastal submarine | 1,080 | 1 March 1933 | Sunk 5 July 1941 |
| Jastrząb | Polish Navy | S (Group I) | submarine | 1,062 | 9 July 1923 | Former USS S-25, transferred to United Kingdom as HMS P551 4 November 1941; loaned to Polish government-in-exile 4 November 1941; sunk 2 May 1942 |
| Junon | French Navy Free French Naval Forces | Minerve | submarine | 856 | 20 September 1937 | Decommissioned 6 December 1954, scrapped 1960 |
| K VII | Royal Netherlands Navy | K V | submarine | 649 | 5 September 1922 | Destroyed in a Japanese bombing on 18 February 1942 |
| K VIII | K VIII | submarine | 810 | 15 September 1922 | Stripped and abandoned in 1943 due lack of crew and age | |
| K IX | Royal Netherlands Navy Royal Australian Navy | 21 June 1923 | Transferred to RAN as HMAS K9 on 22 June 1943 | |||
| K X | Royal Netherlands Navy | 24 September 1923 | Scuttled on 2 March 1942 at Surabaya to avoid being captured by the Japanese | |||
| K XI | K XI | submarine | 828 | 24 March 1925 | Stripped and scuttled 1945 / 1946 | |
| K XII | 19 May 1925 | Sold in 1946 and scrapped in 1951 | ||||
| K XIII | 29 March 1926 | Scuttled on 2 March 1942 to prevent being captured by the Japanese | ||||
| K XIV | K XIV | submarine | 1,045 | 6 July 1933 | Decommissioned 23 April 1946, stricken 1 June 1946 | |
| K XV | 30 December 1933 | Stricken 1 June 1946, sold for scrap December 1950 | ||||
| K XVI | 31 January 1934 | Sunk on 25 December 1941 by a torpedo of the I-166 | ||||
| K XVII | 19 December 1933 | Struck and sunk by a Japanese mine on 21 December 1941 | ||||
| K XVIII | 23 March 1934 | Scuttled on 2 March 1942 in order to prevent Japanese capture | ||||
| Kalev |  Estonian Navy Soviet Navy | Kalev | minelayer submarine | 853 | 12 March 1937 | Captured by Soviet Union 18 September 1940, missing 29 October 1941 |
| Kete | United States Navy | Balao | fleet submarine | 2,391 | 31 July 1944 | Missing after 20 March 1945 |
| Kingfish | United States Navy | Gato | fleet submarine | 2,424 | 20 May 1942 | Sold for scrap 6 October 1960 |
| Kraken | United States Navy | Balao | fleet submarine | 2,391 | 8 September 1944 | Transferred to Spain as Almirante García de los Reyes 24 October 1959; Stricken 1 April 1982; scrapped |
| Krasnogvardyeyets | Soviet Navy | Dekabrist | submarine | 1,354 | 12 July 1929 | Missing after 10 June 1942 |
| L23 | Royal Navy | L | submarine | 1,106 | 31 October 1924 | Paid off May 1946 |
| L26 | submarine | 11 October 1926 | Sunk as target 1 November 1946 | |||
| L27 | training submarine | Scrapped 1944 | ||||
| L'Espoir | French Navy | Redoutable | cruiser submarine | 1,968 | 1 February 1934 | Scuttled 27 November 1942 |
| La Psyché | French Navy | Diane | submarine | 796 | 23 December 1933 | Sunk 8 November 1942 |
| La Sultane | French Navy Free French Naval Forces | Argonaute | submarine | 785 | 20 May 1935 | Joined the Free French Naval Forces December 1942; sold for scrap 14 August 1946 |
| La Sibylle | French Navy | Diane | submarine | 796 | 22 December 1934 | Missing after 8 November 1942 |
| La Vestale | French Navy Free French Naval Forces | Argonaute | submarine | 785 | 18 September 1934 | Joined the Free French Naval Forces December 1942; laid up 1944; sold for scrap 25 March 1946 |
| Lafolè | Regia Marina | Adua | coastal submarine | 843 | 13 August 1938 | Sunk 20 October 1940 |
| Lagarto | United States Navy | Balao | fleet submarine | 2,391 | 14 October 1944 | Sunk 4 May 1945 |
| Lamprey | 17 November 1944 | Transferred to Argentina as Santiago del Estero 21 August 1960; scrapped 1974 | ||||
| Lancetfish | 12 February 1945 | Sank at pier 15 March 1945; never repaired; sold for scrap 20 August 1959 | ||||
| Lapon | Gato | fleet submarine | 2,424 | 23 January 1943 | Transferred to Greece as Poseidon 10 August 1957; retired April 1976 | |
| Le Centaure | French Navy Free French Naval Forces | Redoutable | cruiser submarine | 1,968 | 1 January 1935 | Scrapped June 1952 |
| Le Conquérant | French Navy | Redoutable | 7 September 1936 | Sunk 13 November 1942 | ||
| Le Glorieux | French Navy Free French Naval Forces | Redoutable | 1 June 1934 | Scrapped October 1952 | ||
| Le Héros | French Navy | Redoutable | 12 September 1934 | Sunk 7 May 1942 | ||
| Le Tonnant | 1 June 1937 | Scuttled 15 November 1942 | ||||
| Lembit | Estonian Navy Soviet Navy | Kalev | minelayer submarine | 853 | 14 May 1937 | Captured by Soviet Union 18 September 1940; museum ship 5 May 1985 |
| Leonardo da Vinci | Regia Marina | Marconi | submarine | 1,490 | 7 April 1940 | Sunk 23 May 1943 |
| Ling | United States Navy | Balao | fleet submarine | 2,391 | 8 June 1945 | Stricken 1 December 1971; museum ship |
| Lionfish | 1 November 1944 | Museum ship 30 August 1972 | ||||
| Lizardfish | 30 December 1944 | Transferred to Italy as Evangelista Torricelli 9 January 1960; Sold for scrap 1976 | ||||
| Loggerhead | 9 February 1945 | Sold for scrap 29 August 1969 | ||||
| Luciano Manara | Regia Marina | Bandiera | submarine | 1,080 | 29 July 1930 | Stricken 1 February 1948 |
| Luigi Settembrini | Settembrini | submarine | 1,135 | 29 July 1930 | Sunk in collision 15 November 1944 | |
| Luigi Torelli | Marconi | submarine | 1,490 | 15 May 1940 | Seized by Germany September 1943; renamed UIT-25; seized by Japan May 1945; renamed I-504; surrendered August 1945; scuttled 12 February 1946 | |
| Macabi | United States Navy | Balao | fleet submarine | 2,391 | 29 March 1945 | Transferred to Argentina as Santa Fe 11 August 1960; scrapped 1974 |
| Macallé | Regia Marina | Adua | coastal submarine | 843 | 1 March 1937 | Wrecked and sank 15 June 1940 |
| Mackerel | United States Navy | Mackerel | submarine | 1,190 | 31 March 1941 | Sold for scrap 24 April 1947 |
| Maggiore Baracca | Regia Marina | Marconi | submarine | 1,490 | 10 July 1940 | Sunk 7 September 1941 |
| Malachite | Perla | coastal submarine | 839 | 6 November 1936 | Sunk 9 February 1943 | |
| Manta | United States Navy | Balao | fleet submarine | 2,391 | 18 December 1944 | Sunk as target 16 July 1969 |
| Mapiro | 30 April 1945 | Transferred to Turkey as Piri Reis 18 March 1960; scrapped 1973 | ||||
| Marcantonio Bragadin | Regia Marina | Bragadin | submarine | 981 | 16 November 1931 | Stricken 1 February 1948 |
| Marcantonio Colonna | Pisani | submarine | 1,040 | 10 July 1929 | Decommissioned 16 April 1942; scrapped 1943 | |
| Marcello | Marcello | submarine | 1,313 | 5 March 1938 | Missing from late February 1941 | |
| Marea | Flutto | submarine | 1,093 | 7 May 1943 | Stricken 1 February 1948; transferred to the Soviet Union 7 February 1949 | |
| Marlin | United States Navy | Mackerel | submarine | 1,165 | 1 August 1941 | Sold for scrap 29 March 1946 |
| Marsouin | French Navy Free French Naval Forces | Requin | submarine | 1,132 | 7 September 1927 | Joined Free French Naval Forces ca. December 1942; disarmed April 1944; stricken 28 February 1946 |
| Marsuinul | Royal Romanian Navy | submarine | 620 | May 1943 | Captured by the Soviets in August 1944, returned 1951 and scrapped 1967 | |
| Matchanu |  Royal Thai Navy | Matchanu | submarine | 420 | 19 July 1938 | Scrapped in 1952 |
| Medregal | United States Navy | Tench | fleet submarine | 2,414 | 14 April 1945 | Sold for scrap 13 June 1972 |
| Medusa | Regia Marina | Argonauta | coastal submarine | 1,080 | 25 September 1932 | Sunk 30 January 1942 |
| Méduse | French Navy | Diane | submarine | 796 | 1 September 1932 | Wrecked 10 November 1942 |
| Menhaden | United States Navy | Balao | fleet submarine | 2,391 | 22 June 1945 | Sold for scrap 1988 |
| Mero | 17 August 1945 | Transferred to Turkey as Hızırreis 20 April 1960; discarded 1977 | ||||
| Michele Bianchi | Regia Marina | Marconi | submarine | 1,490 | 15 April 1940 | Sunk 5 July 1941 |
| Minerve | French Navy Free French Naval Forces | Minerve | submarine | 856 | 15 September 1936 | Wrecked 19 September 1945 |
| Mingo | United States Navy | Gato | fleet submarine | 2,424 | 12 February 1943 | Transferred to Japan as Kuroshio 15 August 1955; sunk as target 1973 |
| Mocenigo | Regia Marina | Marcello | submarine | 1,313 | 14 August 1938 | Sunk 13 May 1943 |
| Monge | French Navy | Redoutable | cruiser submarine | 1,968 | 19 June 1932 | Sunk 8 May 1942 |
| Moray | United States Navy | Balao | fleet submarine | 2,391 | 26 January 1945 | Sunk as target 18 June 1970 |
| Morosini | Regia Marina | Marcello | submarine | 1,313 | 9 November 1938 | Missing after 8 August 1942 |
| Morse (Q119) | French Navy | Requin | submarine | 1,132 | 10 February 1928 | Sunk 16 June 1940 |
| Morse (P87) | Free French Naval Forces | V | submarine | 740 | 1 December 1944 | Formerly HMS Vortex; returned to the United Kingdom 17 September 1946; loaned to Denmark as U 3 (later renamed Sælen) 1947; returned to the United Kingdom 16 January 1958 scrapped September 1958 |
| Murena | Regia Marina | Flutto | submarine | 1,093 | 25 August 1943 | Scuttled 9 September 1943; refloated by Germany; renamed UIT-16; destroyed in port 4 September 1944 |
| Muskallunge | United States Navy | Gato | fleet submarine | 2,424 | 15 March 1943 | Transferred to Brazil as Humaitá 18 January 1957; sunk as target 9 July 1968 |
| Naïade | French Navy | Sirène | submarine | 745 | 1927 | Scuttled 27 November 1942 |
| Naiade | Regia Marina | Sirena | coastal submarine | 837 | 14 November 1933 | Sunk 14 December 1940 |
| Nani | Marcello | submarine | 1,313 | 5 September 1938 | Sunk 7 January 1941 | |
| Narodovolets | Soviet Navy | Dekabrist | submarine | 1,354 | 19 May 1929 | Museum ship 1989 |
| Narval | French Navy | Requin | submarine | 1,132 | 23 July 1926 | Sunk 15 December 1940 |
| Narval | Acciaio | coastal submarine | 864 | 2 January 1942 | Formerly Italian submarine Bronzo, captured by Royal Navy 12 July 1943; commissioned as HMS P714; transferred to France 29 January 1944; scrapped 1948 | |
| Narvalo | Regia Marina | Squalo | submarine | 1,107 | 6 December 1930 | Sunk 14 January 1943 |
| Narwhal | Royal Navy | Grampus | submarine | 2,157 | 28 February 1936 | Sunk 23 July 1940 |
| Narwhal | United States Navy | V-5 | submarine | 3,900 | 15 May 1930 | Sold for scrap 16 November 1945 |
| Nautilo | Regia Marina | Flutto | submarine | 1,093 | 26 July 1943 | Captured by Germany 9 September 1943; renamed UIT-19, but not commissioned; sunk 9 January 1944; seized and refloated postwar by Yugoslavia; commissioned 1949 as Sava; scrapped 1971 |
| Nautilus | United States Navy | V-5 | submarine | 3,900 | 1 July 1930 | Sold for scrap 16 November 1945 |
| Nautilus | French Navy | Saphir | minelayer submarine | 925 | 15 July 1931 | Captured by Italy 8 December 1942; sunk 31 January 1943; refloated; not repaired; stricken 12 August 1947 |
| Nebojša | Royal Yugoslav Navy | Hrabri | submarine | 1,164 | 1927 | Scrapped in 1958 |
| Neghelli | Regia Marina | Adua | coastal submarine | 843 | 28 February 1938 | Sunk 19 January 1941 |
| Nereide | Sirena | coastal submarine | 837 | 18 February 1934 | Sunk 13 July 1943 | |
| Nichelio | Acciaio | coastal submarine | 864 | 30 July 1942 | Stricken 1 February 1948; transferred to Soviet Union 1949; scrapped 1960 | |
| O 9 | Royal Netherlands Navy | O 9 | submarine | 656 | 18 January 1926 | Scrapped October 1946 |
| O 10 | 1 September 1926 | Scrapped October 1946 | ||||
| O 11 | 18 January 1926 | Sunk in 1940 after taking damage from a collision | ||||
| O 12 | Royal Netherlands Navy Kriegsmarine | O 12 | submarine | 754 | 20 July 1931 | Scuttled in 1940, raised by Nazi Germany's Kriegsmarine and taken into service as U-D2 |
| O 13 | Royal Netherlands Navy | 1 October 1931 | Lost during patrol in the North Sea on 25 June 1940 | |||
| O 14 | 4 March 1932 | Decommissioned in 1943 due to a lack of replacement engines | ||||
| O 15 | 28 July 1932 | Paid off 2 October 1946 | ||||
| O 16 | O 16 | submarine | 1,194 | 27 January 1936 | Sunk by mine on 15 December 1941 | |
| O 19 | O 19 | submarine | 1,491 | 22 September 1938 | Scuttled on 10 July 1945 | |
| O 20 | 28 August 1939 | Sunk 19 December 1941 | ||||
| O 21 | O 21 | submarine | 1,205 | 10 May 1940 | Sold for scrap 24 January 1958 | |
| O 22 | 10 May 1940 | Lost during a patrol in the North Sea in 1940 | ||||
| O 23 | 13 May 1940 | Sold for scrap April 1949 | ||||
| O 24 | 13 May 1940 | Sold for scrap 1963 | ||||
| O 25 | Royal Netherlands Navy Kriegsmarine | 8 June 1941 | Captured during the invasion of the Netherlands and commissioned in the Kriegsmarine as U-D3 | |||
| O 26 | 28 January 1941 | Captured during the invasion of the Netherlands and commissioned in the Kriegsmarine as U-D4 | ||||
| O 27 | 26 September 1941 | Captured during the invasion of the Netherlands and commissioned in the Kriegsmarine as U-D5 | ||||
| O-2 | United States Navy | O | submarine | 629 | 19 October 1918 | Sold for scrap 16 November 1945 |
| O-3 | 13 June 1918 | Sold for scrap 4 September 1946 | ||||
| O-4 | 29 May 1918 | Decommissioned 20 September 1945, scrapped 1 February 1946 | ||||
| O-6 | 12 June 1918 | Sold for scrap 4 September 1946 | ||||
| O-7 | 4 July 1918 | Sold for scrap 22 January 1946 | ||||
| O-8 | 11 July 1918 | Sold for scrap 4 September 1946 | ||||
| O-9 | 27 July 1918 | Foundered 20 June 1941 | ||||
| O-10 | 17 August 1918 | Sold for scrap 21 August 1946 | ||||
| Oberon | Royal Navy | Odin | submarine | 1,922 | 24 August 1927 | Paid off 5 July 1944 |
| Odax | United States Navy | Tench | fleet submarine | 2,414 | 11 July 1945 | Transferred to Brazil as Rio de Janeiro 8 July 1972; scrapped 1981 |
| Odin | Royal Navy | Odin | submarine | 2,038 | 21 December 1929 | Sunk 14 June 1940 |
| Ouessant | French Navy | Redoutable | cruiser submarine | 1,968 | 1 January 1939 | Scuttled 18 June 1940 |
| Olympus | Royal Navy | Odin | submarine | 2,038 | 14 June 1930 | Sunk 8 May 1942 |
| Onice | Regia Marina | Perla | coastal submarine | 839 | 1 September 1936 | Stricken 1 February 1948 |
| Ondina | Sirena | coastal submarine | 837 | 19 September 1934 | Sunk 11 July 1942 | |
| Ondine | French Navy Free French Naval Forces | Orion | submarine | 775 | 5 July 1932 | Stricken April 1943 and dismantled for spare parts |
| Oréade | French Navy | Diane | submarine | 796 | 14 December 1933 | Sunk 8 November 1942 |
| Orion | French Navy Free French Naval Forces | Orion | submarine | 775 | 5 July 1932 | Stricken April 1943 and dismantled for spare parts |
| Orphée | French Navy Free French Naval Forces | Diane | submarine | 796 | 8 June 1933 | Stricken 15 April 1946 |
| Orpheus | Royal Navy | Odin | submarine | 2,038 | 23 September 1930 | Sunk 19 June 1940 |
| Orzeł | Polish Navy | Orzeł | submarine | 1,473 | 2 February 1939 | Lost 8 June 1940 |
| Osiris | Royal Navy | Odin | submarine | 2,038 | 25 January 1929 | Paid off 7 March 1945 |
| Osvetnik | Royal Yugoslav Navy Regia Marina | Ostevnik | submarine | 809 | 14 January 1929 | Captured by Italy 1941, scuttled by Germany in 1943 |
| Oswald | Royal Navy | Odin | submarine | 2,038 | 1 May 1929 | Sunk 1 August 1940 |
| Otaria | Regia Marina | Glauco | submarine | 1,305 | 20 October 1935 | Stricken 1 February 1948 |
| Otus | Royal Navy | Odin | submarine | 2,038 | 5 July 1929 | Paid off March 1946 |
| Otway | 1,922 | 15 June 1927 | Paid off 1945 | |||
| Oxley | 1,922 | 1 April 1927 | Sunk by friendly fire 10 September 1939 | |||
| P31 | U | submarine | 730 | 2 April 1941 | Renamed Ullswater February 1943; renamed Uproar April 1943; sold for scrap 13 February 1946 | |
| P32 | 3 May 1941 | Sunk 18 August 1941 | ||||
| P33 | 30 May 1941 | Missing after 6 August 1941 | ||||
| P36 | 24 September 1941 | Sunk 1 April 1942 | ||||
| P38 | 17 October 1941 | Sunk 23 February 1942 | ||||
| P39 | 16 November 1941 | Damaged beyond repair 26 March 1942; scrapped 1954 | ||||
| P48 | 18 June 1942 | Sunk 25 December 1942 | ||||
| P222 | S (Third Group) | submarine | 990 | 4 March 1942 | Sunk 12 December 1942 | |
| P311 | T | submarine | 1,560 | 7 August 1942 | Sunk 8 January 1943 | |
| P511 | R | training submarine | 680 | 17 April 1919 | Former USS R-3, transferred to United Kingdom 4 November 1941; scrapped 1948 | |
| P512 | 17 August 1918 | Former USS R-17, transferred to United Kingdom 9 March 1942; sold for scrap 6 November 1945 | ||||
| P514 | 7 October 1918 | Former USS R-19, transferred to United Kingdom 9 March 1942; sunk 21 June 1942 | ||||
| P551 | S (Holland design) | submarine | 1,062 | 9 July 1923 | Former USS S-25, transferred to United Kingdom 4 November 1941; loaned to Polish government-in-exile as Jastrząb 4 November 1941; sunk 2 May 1942 | |
| P552 | S (Navy design) | submarine | 1,092 | 5 June 1920 | Former USS S-1, transferred to United Kingdom 20 April 1942; sold for scrap 14 September 1945 | |
| P553 | S (Holland design) | submarine | 1,062 | 24 August 1921 | Former USS S-21, transferred to United Kingdom 14 September 1942; sunk as target 23 March 1945 | |
| P554 | 23 June 1924 | Former USS S-22, transferred to United Kingdom 19 June 1942; sold for scrap 16 November 1945 | ||||
| P555 | 24 August 1923 | Former USS S-24, transferred to United Kingdom 10 August 1942; scuttled 25 August 1947 | ||||
| P556 | 22 May 1924 | Former USS S-29, transferred to the United Kingdom 5 June 1942; sold for scrap, 24 January 1947 | ||||
| P611 | Oruç Reis | submarine | 856 | 1 December 1941 | Transferred to Turkey as Oruç Reis 9 May 1942; scrapped 1957 | |
| P612 | 7 January 1942 | Transferred to Turkey as Murat Reis 16 May 1942; scrapped 1957 | ||||
| P614 | 10 March 1942 | Transferred to Turkey 1945; commissioned as Burak Reis 17 January 1946; scrapped 1957 | ||||
| P615 | 3 April 1942 | Sunk 18 April 1943 | ||||
| P714 | Acciaio | coastal submarine | 864 | 2 January 1942 | Formerly Italian submarine Bronzo, captured by Royal Navy 12 July 1943; transferred to France as Narval 29 January 1944; scrapped 1948 | |
| Paddle | United States Navy | Gato | fleet submarine | 2,424 | 29 March 1943 | Transferred to Brazil as Riachuelo 18 January 1957; sunk as target ca. 30 June 1968 |
| Pallas | French Navy | Minerve | submarine | 856 | 12 June 1939 | Scuttled 9 November 1942 |
| Pampanito | United States Navy | Balao | fleet submarine | 2,391 | 6 November 1943 | Museum ship 21 November 1975 |
| Pandora | Royal Navy | Parthian | submarine | 2,040 | 30 June 1930 | Sunk 1 April 1942, scrapped 1955 |
| Komissar | Soviet Navy | Bars | submarine | 1,354 | 1916 | Converted to harbor training ship 1941 |
| Parche | United States Navy | Balao | fleet submarine | 2,391 | 20 November 1943 | Sold for scrap 18 June 1970 |
| Pargo | Gato | fleet submarine | 2,424 | 26 April 1943 | Sold for scrap 16 May 1961 | |
| Parthian | Royal Navy | Parthian | submarine | 2,040 | 30 June 1930 | Sunk August 1943 |
| Pascal | French Navy | Redoutable | cruiser submarine | 1,968 | 10 September 1931 | Scuttled 27 November 1942; refloated; sunk 11 March 1944 |
| Pasteur | 1 September 1932 | Scuttled 18 June 1940 | ||||
| Pégase | 19 June 1932 | Decommissioned 1 January 1944; scrapped 1951 | ||||
| Perch (SS-176) | United States Navy | Porpoise | fleet submarine | 1,997 | 19 November 1936 | Scuttled 3 March 1942 |
| Perch (SS-313) | Balao | fleet submarine | 2,391 | 7 January 1944 | Sold for scrap 15 January 1973 | |
| Perla | Regia Marina Royal Navy Hellenic Navy | Perla | coastal submarine | 846 | 8 July 1936 | Captured by UK as HMS P-712 9 July 1942, to Greece as Matrozos 1943, stricken 1947 |
| Perle | French Navy Free French Naval Forces | Saphir | minelayer submarine | 925 | 1 March 1937 | Sunk 8 July 1944 |
| Permit | United States Navy | Porpoise | fleet submarine | 1,997 | 17 March 1937 | Sold for scrap 28 June 1958 |
| Persée | French Navy | Redoutable | cruiser submarine | 1,968 | 10 June 1934 | Sunk 23 September 1940 |
| Perseus | Royal Navy | Parthian | submarine | 2,040 | 15 April 1930 | Sunk 6 December 1941. |
| Peto | United States Navy | Gato | fleet submarine | 2,424 | 21 November 1942 | Sold for scrap 29 November 1960 |
| Phoenix | Royal Navy | Parthian | submarine | 2,040 | 3 February 1931 | Sunk 16 July 1940 |
| Phoque | French Navy | Requin | submarine | 1,132 | 7 May 1928 | Captured by Italy 8 December 1942; renamed FR 111; sunk 28 February 1943 |
| Phlai-chumphon | Royal Thai Navy | Matchanu | submarine | 420 | 19 July 1938 | Scrapped 1952 |
| Pickerel | United States Navy | Porpoise | fleet submarine | 1,997 | 26 January 1937 | Sunk 3 April 1943 |
| Picuda | Balao | fleet submarine | 2,391 | 16 October 1943 | Transferred to Spain as Narciso Monturiol 1 October 1972; Stricken 30 April 1977 | |
| Pier Capponi | Regia Marina | Mameli | submarine | 993 | 19 January 1929 | Sunk 31 March 1941 |
| Pietro Calvi | Calvi | cruiser submarine | 2,028 | 16 October 1935 | Sunk 14 July 1942 | |
| Pietro Micca | minelayer submarine | 1,883 | 1 October 1935 | Sunk 29 July 1943 | ||
| Pike | United States Navy | Porpoise | fleet submarine | 1,934 | 2 December 1935 | Sold for scrap 14 January 1957 |
| Pilotfish | Balao | fleet submarine | 2,391 | 16 December 1943 | Sunk as target 25 July 1946 | |
| Pintado | 1 January 1944 | Sold for scrap 19 February 1969 | ||||
| Pipefish | 22 January 1944 | Sold for scrap 4 February 1969 | ||||
| Piper | 23 August 1944 | Sold for scrap June 1971 | ||||
| Pipinos | Royal Hellenic Navy | V | submarine | 740 | 1 November 1943 | Formerly HMS Veldt; returned to United Kingdom 10 December 1957; scrapped February 1958 |
| Piranha | United States Navy | Balao | fleet submarine | 2,391 | 5 February 1944 | Sold for scrap 11 August 1970 |
| Plaice | 12 February 1944 | Transferred to Brazil as Bahia 7 September 1963; scrapped 1973 | ||||
| Platino | Regia Marina | Acciaio | coastal submarine | 864 | 2 October 1941 | Stricken 1 February 1948 |
| Plunger | United States Navy | Porpoise | fleet submarine | 1,997 | 19 November 1936 | Sold for scrap 22 April 1957 |
| Pogy | Gato | fleet submarine | 2,424 | 10 January 1943 | Sold for scrap 1 May 1959 | |
| Pollack | Porpoise | fleet submarine | 1,997 | 15 January 1937 | Sold for scrap 2 February 1947 | |
| Pomfret | Balao | fleet submarine | 2,391 | 19 February 1944 | Transferred to Turkey as Oruçreis 1 July 1971; retired 1987 | |
| Pompano | Porpoise | fleet submarine | 1,997 | 12 June 1937 | Lost September 1943 | |
| Pompon | Gato | fleet submarine | 2,424 | 17 March 1943 | Sold for scrap 22 December 1960 | |
| Poncelet | French Navy | Redoutable | cruiser submarine | 1,968 | 1 September 1932 | Scuttled 7 November 1940 |
| Porfido | Regia Marina | Acciaio | coastal submarine | 864 | 24 January 1942 | Sunk 6 December 1942 |
| Porpoise | United States Navy | Porpoise | fleet submarine | 1,934 | 15 August 1935 | Sold for scrap 14 May 1957 |
| Porpoise | Royal Navy | Grampus | submarine | 2,035 | 11 March 1933 | Sunk 19 January 1945 |
| Poseidon | Parthian | submarine | 2,040 | 5 May 1930 | Sunk in accidental collision with a merchant ship 9 June 1931 | |
| Provana | Regia Marina | Marcello | submarine | 1,313 | 25 June 1938 | Sunk 16 June 1940 |
| Protée | French Navy Free French Naval Forces | Redoutable | cruiser submarine | 1,968 | 1 November 1932 | Sunk 20 December 1943 |
| Proteus | Royal Navy | Parthian | submarine | 2,040 | 5 May 1930 | Scrapped March 1946 |
| Puffer | United States Navy | Gato | fleet submarine | 2,424 | 27 April 1943 | Sold for scrap 3 December 1960 |
| Queenfish | Balao | fleet submarine | 2,391 | 11 March 1944 | Sunk as target 14 August 1963 | |
| Quidora | Chilean Navy | H | submarine | 434 | 1917 | Scrapped 1945 |
| Quillback | United States Navy | Tench | fleet submarine | 2,414 | 29 December 1944 | Sold for scrap 21 March 1974 |
| R-1 | R | coastal submarine | 680 | 16 December 1918 | Sold for scrap 16 March 1946 | |
| R-2 | 24 January 1919 | Sold for scrap 28 September 1945 | ||||
| R-3 | 28 March 1919 | Transferred to United Kingdom as P511 4 November 1941; scrapped 1948 | ||||
| R-4 | 17 April 1919 | Sold for scrap January 1946 | ||||
| R-5 | 15 April 1919 | Sold for scrap 22 August 1946 | ||||
| R-6 | 1 May 1919 | Sold for scrap March 1946 | ||||
| R-7 | 12 June 1919 | Sold for scrap September 1946 | ||||
| R-9 | 30 July 1919 | Sold for scrap February 1946 | ||||
| R-10 | 20 August 1919 | Sold for scrap January 1946 | ||||
| R-11 | 5 September 1919 | Scrapped 1948 | ||||
| R-12 | 23 September 1919 | Sank 12 June 1943 | ||||
| R-13 | 17 October 1919 | Sold for scrap 13 March 1946 | ||||
| R-14 | 24 December 1919 | Scrapped 1946 | ||||
| R-15 | 27 July 1918 | Sold for scrap October 1945 | ||||
| R-16 | 5 August 1918 | Sold for scrap March 1946 | ||||
| R-17 | 17 August 1918 | Transferred to United Kingdom as P512 9 March 1942; sold for scrap 6 November 1945 | ||||
| R-18 | 11 September 1918 | Sold for scrap 1946 | ||||
| R-19 | 7 October 1918 | Transferred to United Kingdom as P514 9 March 1942; sunk 21 June 1942 | ||||
| R-20 | 26 October 1918 | Sold for scrap 13 March 1946 | ||||
| Rainbow | Royal Navy | Rainbow | submarine | 2,030 | 18 January 1932 | Sunk 4 October 1940 in collision |
| Rasher | United States Navy | Gato | fleet submarine | 2,424 | 8 June 1943 | Sold for scrap 7 August 1974 |
| Raton | 13 July 1943 | Sold for scrap 12 October 1973 | ||||
| Ray | 27 July 1943 | Sold for scrap 18 December 1960 | ||||
| Razorback | Balao | fleet submarine | 2,391 | 3 April 1944 | Transferred to Turkey as Muratreis 30 November 1970; museum ship 15 May 2005 | |
| Rechinul | Royal Romanian Navy | Rechinul | submarine | 789 | May 1943 | Captured by the Soviets in August 1944, sunk by accident February 1945 |
| Redfin | United States Navy | Gato | fleet submarine | 2,424 | 31 August 1943 | Sold for scrap 31 March 1971 |
| Redfish | Balao | fleet submarine | 2,391 | 12 April 1944 | Sunk as target 6 February 1969 | |
| Redoutable | French Navy | Redoutable | cruiser submarine | 1,968 | 10 July 1931 | Scuttled 27 November 1942; refloated 16 May 1943; sunk 11 March 1944 |
| Regent | Royal Navy | Rainbow | submarine | 2,030 | 11 November 1930 | Sunk 18 April 1943 |
| Reginaldo Giuliani | Regia Marina | Liuzzi | submarine | 1,484 | 3 February 1940 | Seized by Germany 8 September 1943; renamed UIT-23; sunk 18 February 1944 |
| Regulus | Royal Navy | Rainbow | submarine | 2,030 | 7 December 1930 | Sunk 6 December 1940 |
| Remo | Regia Marina | R | transport submarine | 2,520 | 19 June 1943 | Sunk 15 July 1943 |
| Requin | French Navy | Requin | submarine | 1,132 | 28 May 1926 | Captured by Italy 8 December 1942; renamed FR 113; captured by Germany 9 September 1943; sold for scrap 1944 |
| Requin | United States Navy | Tench | fleet submarine | 2,414 | 28 April 1945 | Museum ship 1972 |
| Revolutsioner | Soviet Navy | Dekabrist | submarine | 1,354 | 12 March 1929 | Missing after 1 December 1943 |
| Ro-31 | Imperial Japanese Navy | Kaichū V type | training submarine | 1,030 | 10 May 1927 | Scuttled 5 April 1946 |
| Ro-33 | Kaichū VI type | submarine | 1,200 | 7 October 1935 | Sunk 29 August 1942 | |
| Ro-34 | 31 May 1937 | Sunk 7 April 1943 | ||||
| Ro-35 | Kaichū VII type | submarine | 1,447 | 25 March 1943 | Sunk 25 August 1943 | |
| Ro-36 | 27 May 1943 | Sunk 13 June 1944 | ||||
| Ro-37 | 30 June 1943 | Sunk 22 January 1944 | ||||
| Ro-38 | 24 July 1943 | Missing after 19 November 1943 | ||||
| Ro-39 | 12 September 1943 | Sunk 1 February 1944 | ||||
| Ro-40 | 28 September 1943 | Sunk 16 February 1944 | ||||
| Ro-41 | 26 November 1943 | Sunk 23 March 1945 | ||||
| Ro-42 | 31 August 1943 | Sunk 11 June 1944 | ||||
| Ro-43 | 16 December 1943 | Sunk 26 February 1945 | ||||
| Ro-44 | 13 September 1943 | Sunk 16 June 1944 | ||||
| Ro-45 | 11 January 1944 | Sunk 30 April 1944 | ||||
| Ro-46 | 19 February 1944 | Missing after 17 April 1945 | ||||
| Ro-47 | 31 January 1944 | Sunk 26 September 1944 | ||||
| Ro-48 | 31 March 1944 | Sunk 19 July 1944 | ||||
| Ro-49 | 19 May 1944 | Missing after 25 March 1945 | ||||
| Ro-50 | 31 July 1944 | Scuttled 1 April 1946 | ||||
| Ro-55 | 30 September 1944 | Sunk 7 February 1945 | ||||
| Ro-56 | 15 November 1944 | Sunk 9 April 1945 | ||||
| Ro-57 | Type L3 | training submarine | 1,102.7 | 30 July 1922 | Scrapped 1946 | |
| Ro-58 | 25 November 1922 | Scrapped 1946 | ||||
| Ro-59 | 20 March 1923 | Scrapped 1946 | ||||
| Ro-60 | Type L4 | submarine | 1,301 | 17 September 1923 | Wrecked 29 December 1941 | |
| Ro-61 | 9 February 1924 | Sunk 31 August 1942 | ||||
| Ro-62 | 24 July 1924 | Scuttled May 1946 | ||||
| Ro-63 | 20 December 1924 | Scuttled May 1946 | ||||
| Ro-64 | 30 April 1925 | Sunk 12 April 1945 | ||||
| Ro-65 | 30 June 1926 | Sunk in diving accident 3 November 1942 | ||||
| Ro-66 | 28 July 1927 | Sunk in collision 17 December 1941 | ||||
| Ro-67 | 15 December 1926 | Scrapped 1946 | ||||
| Ro-68 | 29 October 1925 | Scuttled 30 April 1946 | ||||
| Ro-100 | Ko type | coastal submarine | 782 | 23 September 1942 | Sunk 25 November 1943 | |
| Ro-101 | 31 October 1942 | Sunk 15 September 1943 | ||||
| Ro-102 | 17 November 1942 | Missing after 9 May 1943 | ||||
| Ro-103 | 21 October 1942 | Missing after 28 July 1943 | ||||
| Ro-104 | 25 February 1943 | Sunk 23 May 1944 | ||||
| Ro-105 | 5 March 1943 | Sunk 31 May 1944 | ||||
| Ro-106 | 26 December 1942 | Sunk 22 May 1944 | ||||
| Ro-107 | 26 December 1942 | Missing after 6 July 1943 | ||||
| Ro-108 | 20 April 1943 | Sunk 26 May 1944 | ||||
| Ro-109 | 30 April 1943 | Sunk 25 April 1945 | ||||
| Ro-110 | 6 July 1943 | Sunk 11 February 1944 | ||||
| Ro-111 | 19 July 1943 | Sunk 10 June 1944 | ||||
| Ro-112 | 14 September 1943 | Sunk 11 February 1945 | ||||
| Ro-113 | 12 October 1943 | Sunk 13 February 1945 | ||||
| Ro-114 | 20 November 1943 | Sunk 17 June 1944 | ||||
| Ro-115 | 30 November 1943 | Sunk 1 February 1945 | ||||
| Ro-116 | 21 January 1944 | Sunk 24 May 1944 | ||||
| Ro-117 | 31 January 1944 | Sunk 17 June 1944 | ||||
| Ro-500 (ex-U-511) | Type IXC | submarine | 1,213 | 16 September 1943 | Scuttled 30 April 1946 | |
| Ro-501 (ex-U-1224) | Type IXC/40 | submarine | 1,237 | 15 February 1944 | Sunk 13 May 1944 | |
| Robalo | United States Navy | Gato | fleet submarine | 2,424 | 28 September 1943 | Sunk 26 July 1944 |
| Rock | 26 October 1943 | Sold for scrap 17 August 1972 | ||||
| Romolo | Regia Marina | R | transport submarine | 2,520 | 19 June 1943 | Sunk 18 July 1943 |
| Roncador | United States Navy | Balao | fleet submarine | 2,391 | 27 March 1945 | Stricken 1971; scrapped ca. 1982 |
| Ronis |  Latvian Naval Forces Soviet Navy | Ronis | submarine | 514 | 1927 | Captured by Soviet Union 13 August 1940, scuttled 24 June 1941 |
| Ronquil | United States Navy | Balao | fleet submarine | 2,391 | 22 April 1944 | Transferred to Spain as Isaac Peral 1 July 1971; decommissioned 3 April 1984 |
| Rorqual | Royal Navy | Grampus | submarine | 2,157 | 10 February 1937 | Scrapped 1946 |
| Rover | Rainbow | submarine | 2,030 | 29 January 1931 | Scrapped 1946 | |
| Rubino | Regia Marina | Sirena | coastal submarine | 837 | 21 March 1934 | Sunk 29 June 1940 |
| Rubis | French Navy Free French Naval Forces | Saphir | minelayer submarine | 925 | 4 April 1933 | Scuttled 31 January 1958 |
| Rucumilla | Chilean Navy | H | submarine | 434 | 1917 | Scrapped 1945 |
| Ruggiero Settimo | Regia Marina | Settembrini | submarine | 1,135 | 25 April 1932 | Stricken 23 March 1947 |
| Runner (SS-275) | United States Navy | Gato | fleet submarine | 2,424 | 30 July 1942 | Missing June 1943 |
| Runner (SS-476) | Tench | fleet submarine | 2,414 | 6 February 1945 | Sold for scrap 19 June 1973 | |
| Ryś | Polish Navy | Wilk | submarine | 1,250 | 1932 | Interned 17 September 1939, decommissioned 1955, scrapped 1956 |
| S-1 | Soviet Navy | Srednyaya (IX series) | submarine | 1,050 | 11 September 1936 | scuttled 23 June 1941 |
| S-1 | United States Navy | S (Holland design) | submarine | 1,062 | 5 June 1920 | Transferred to the United Kingdom as P552 20 April 1942; sold for scrap 14 September 1945 |
| S-2 | Soviet Navy | Srednyaya (IX series) | submarine | 1,050 | 23 September 1936 | Sunk 3 January 1940 |
| S-3 | 8 July 1938 | Sunk 24 June 1941 | ||||
| S-4 | Srednyaya (IX-bis series) | submarine | 1,050 | 30 October 1939 | Sunk 7 January 1945 | |
| S-5 | 30 October 1939 | Sunk 28 August 1941 | ||||
| S-6 | 30 October 1939 | Missing after 6 August 1941 | ||||
| S-7 | 30 June 1940 | Sunk 21 October 1942 | ||||
| S-8 | 30 June 1940 | Missing after 11 October 1941 | ||||
| S-9 | 31 October 1940 | Missing August 1943 | ||||
| S-10 | 25 December 1940 | Sunk around 28 June 1941 | ||||
| S-11 | 27 June 1941 | Sunk 2 August 1941, raised 1955, scrapped 1957–1958 | ||||
| S-11 | United States Navy | S (Navy design) | submarine | 1,092 | 11 January 1923 | Sold for scrap 28 October 1945 |
| S-12 | Soviet Navy | Srednyaya (IX-bis series) | submarine | 1,050 | 24 July 1941 | Missing 1 August 1943 |
| S-12 | United States Navy | S (Navy design) | submarine | 1,092 | 30 April 1923 | Sold for scrap 28 October 1945 |
| S-13 |