Ship prefixes in the United States Navy have consistently been "United States Type," where Type was "Ship," "Sloop," "Bark," and so on. (The types other than "Ship" have fallen out of use.) Hull classification symbols -- "BB" for battleships and so on -- were haphazard, but in 1907 were standardized by executive order of President Theodore Roosevelt.
| Country | Service | Prefix | Meaning | |
|---|---|---|---|---|
| generic | all | MV | Motor Vessel | |
| generic | all | PS | Paddle Steamer | |
| generic | all | SS | Steam Ship | |
| generic | all | SV | Sailing Vessel | |
| Argentina | Argentine Navy | ARA | Armada de la Republica Argentina | |
| Australia | Royal Australian Navy | HMAS | His/Her Majesty's Australian Ship | |
| Bahamas | Bahamian Defense Force | HMBS | His/Her Majesty's Bahamian Ship | |
| Bangladesh | Bangladesh Navy | BNS | Bangladesh Naval Ship | |
| Barbados | Barbadan Defence Force | HMBS | His/Her Majesty's Barbadian Ship | |
| Belgium | Belgian Navy | BNS | Belgium Naval Ship (NATO prefix) | |
| Canada | Canadian Forces Maritime Command | HMCS | His/Her Majesty's Canadian Ship | |
| Canada | Canadian Coast Guard | CCGS | Canadian Coast Guard Ship | |
| Colombia | Armada Nacional | ARC | Armada de la Republica de Colombia | |
| Denmark | Royal Danish Navy | HDMS (Danish: KDM) | His/Her Danish Majesty's Ship (Danish: Kongelige Danske Marine) | |
| Ecuador | Military of Ecuador | BAE | Buque de la Armada de Ecuador | |
| Fiji | Military of Fiji | RFNS | Republic of Fiji Naval Ship | |
| France | French Navy | FS | French Ship (NATO designation) | |
| German Empire | Kaiserliche Marine | SM U-## | Seiner Majestät Unterseeboot | |
| German Empire | Kaiserliche Marine | SMS | Seiner Majestät Schiff | |
| Germany | Bundesmarine | FGS | Federal German Ship (NATO designation) | |
| Great Britain | Ships carrying mail | RMS | Royal Mail Steamer | |
| Great Britain | Royal Fleet Auxiliary | RFA | Royal Fleet Auxiliary | |
| Great Britain | Royal Navy | HMS | His/Her Majesty's Ship | |
| Great Britain | Government research ships | RRS | Royal Research Ship | |
| Greece | Hellenic Navy | HS | Hellenic Ship (NATO designation) | |
| Guyana | ?? | GDFS | Guyanan Defense Forces Ship | |
| India | Indian Navy (pre-Republic) | HMINS | His/Her Majesty's Indian Naval Ship | |
| India | Indian Navy | INS | Indian Naval Ship | |
| Israel | Israeli Navy | INS | Israeli Naval Ship | |
| Japan | Imperial Japanese Navy | HIJMS | His Imperial Japanese Majesty's Ship | |
| Japan (after WWII) | Japanese Maritime Self Defense Force | JDS | JMSDF Defense Ship | |
| Kenya | ? | KNS | Kenyan Naval Ship | |
| Malaysia | Royal Malaysian Navy | KD | Kapal Di-Raja - His Majesty's Ship | |
| Netherlands | Royal Netherlands Navy | HNLMS (Dutch: Hr.Ms. or Z.Ms.) | His/Her Majesty's Netherlands Ship (Dutch: Hare Majesteit's or Zijne Majesteit's) | |
| New Zealand | Royal New Zealand Navy | HMNZS | His/Her Majesty's New Zealand Ship | |
| Nigeria | ? | NNS | Nigerian Naval Ship | |
| Norway | Royal Norwegian Navy | KNM | Kongelige Norske Marine | |
| Norway | Norwegian Coast Guard | KV | Kystvakt | |
| Oman | ? | SNV | Sultanate Naval Vessel | |
| Pakistan | Pakistani Navy | PNS | Pakistani Naval Ship | |
| Papua New Guinea | ? | HMPNGS | Her Majesty's Papua New Guinea Ship | |
| Peru | Peruvian Navy | BAP | Buque Armada Peruana | |
| Philippines | Philippine Navy | BRP | Barka ng Republika ng Pilipinas | |
| Poland | Polish Navy | ORP | Polish Republic Naval Ship
(Polish: Okręt Rzeczypospolitej Polskiej) |
|
| Portugal | ? | NRP | Portuguese Republic Ship (Navio da República Portuguesa) | |
| Saudi Arabia | Saudi Navy | HMS | His Majesty's Ship -- the same as the Royal Navy | |
| Singapore | Republic of Singapore Navy | RSS | Republic of Singapore Ship | |
| South Africa | South African Navy | SAS | South African Ship | |
| Spain | Armada Espanola | SPS | Spanish Naval Ship | |
| Sri Lanka | Sri Lanka Navy | SLNS | Sri Lanka Naval Ship | |
| Sweden | Royal Swedish Navy | HMS | His Majesty's Ship -- the same as the Royal Navy | |
| Thailand | Royal Thai Navy | HTMS | His Thai Majesty's Ship | |
| Turkey | Turkish Navy | TCG | Türkiye Cumhuriyeti Gemisi | |
| Trinidad & Tobago | ? | TTS | Trinidad & Tobago Ship | |
| United States | U.S. Navy | USS | United States Ship | |
| United States | U.S. Navy Military Sealift Command | USNS | United States Naval Ship | |
| United States | U.S. Coast Guard | USCGC | United States Coast Guard Cutter | |
| Uruguay | Uruguay Navy | ROU | Republica del Oriental Uruguay |
Occasionally writers will prefix a ship's name with an abbreviation of its nationality in their own language, such as "IJN" for Teikoku Nihon Kaigun, but that usage is deprecated.
In the Royal Netherlands Navy, "HNLMS" is the prefix in English, but in Dutch translates to "Hr.Ms." or "Z.Ms.". Thus "Hr.Ms." should never be used in an English document; nevertheless it is often seen on the World Wide Web.
United States ships that have not been commissioned in the Navy yet don't hold the title of USS, it holds the title of PCU (Pre-commissioned unit) For example, the shipyard is building the new aircraft carrier-- The Neversail. For the day the keel is laid to the date it is commissioned, it is called the PCU Neversail. Once it enter active service in the fleet and is commissioned it will be referred to as the USS Neversail. See also the WikiProject Ships.