# Equivalent Royal Navy ranks in the Merchant Navy

These are the equivalent Merchant Navy and Royal Navy ranks officially recognised by the British Government in the Second World War.
Naval Auxiliaries were members of the Royal Fleet Auxiliary and crews of Admiralty cable ships or merchant ships or commissioned rescue tugs requisitioned by the Royal Navy and coming under naval discipline.
| RN rank | Deck Department | Engine Room Department | Catering Department |
| Commander | Master (over 10,000 tons) | Chief Engineer (over 10,000 tons) | |
| Lieutenant-Commander | Master (2,501-10,000 tons or up to 2,500 tons if home trade passenger ship of speed 15 knots or more or cable ship) First Mate (over 10,000 tons) Surgeon (over 10,000 tons) | Chief Engineer (2,501-10,000 tons or up to 2,500 tons if home trade passenger ship of speed 15 knots or more) Certificated Second Engineer (over 10,000 tons) | Purser (Naval Auxiliary; over 10,000 tons or 2,501-10,000 tons if at least two assistant pursers carried) |
| Lieutenant | Master (up to 2,500 tons unless home trade passenger ship of speed 15 knots or more or cable ship or home trade cargo ship up to 1,000 tons) First Mate (2,501-10,000 tons or up to 2,500 tons if home trade passenger ship of speed 15 knots or more or cable ship or Naval Auxiliary holding Master's Certificate) Certificated Second Mate (over 10,000 tons or Naval Auxiliary over 30 holding Master's Certificate) Certificated Third Mate (Naval Auxiliary; over 10,000 tons holding Master's Certificate) Surgeon (up to 10,000 tons) | Chief Engineer (up to 2,500 tons unless home trade passenger ship of speed 15 knots or more or home trade cargo ship up to 1,000 tons) Certificated Second Engineer (2,501-10,000 tons or up to 2,500 tons if home trade passenger ship of speed 15 knots or more or cable ship) Certificated Third Engineer (over 10,000 tons) Certificated Chief Refrigerating Engineer (holding 1st Class Certificate) Chief (or only) Electrician (cable ship or if 4 or more electricians carried) | Purser (over 10,000 tons or Naval Auxiliary 2,501-10,000 tons if at least one assistant purser carried) Senior Assistant Purser (Naval Auxiliary; over 10,000 tons or 2,501-10,000 tons if 3 or more pursers carried) |
| Sub-Lieutenant | Certificated Master (home trade cargo ship up to 1,000 tons) First Mate (up to 2,500 tons unless home trade passenger ship of speed 15 knots or more or cable ship or home trade cargo ship up to 1,000 tons) Certificated Second Mate (up to 10,000 tons unless home trade cargo ship up to 1,000 tons) Certificated Third Mate (except home trade cargo ship up to 1,000 tons) Certificated Junior Mate (except home trade cargo ship up to 1,000 tons) Radio Officer or Wireless Telegraphist (3 or more years' service) | Certificated Chief Engineer (home trade cargo ship up to 1,000 tons) Chief Engineer (Naval Auxiliary; commissioned rescue tug if not holding First Engineer's Certificate) Certificated Second Engineer (up to 2,500 tons unless home trade passenger ship of speed 15 knots or more or cable ship or home trade cargo ship up to 1,000 tons) Certificated Third Engineer (up to 10,000 tons unless home trade cargo ship up to 1,000 tons) Certificated Fourth Engineer (except home trade cargo ship up to 1,000 tons) Certificated Junior Engineer (except home trade cargo ship up to 1,000 tons) Certificated Chief Refrigerating Engineer (holding 2nd Class Certificate) Certificated Refrigerating Engineer Chief Electrician (except cable ship) Second Electrician (Naval Auxiliary; ship carrying 4 or more electricians) Electrician (cable ship also carrying Chief Electrician) Certificated Boilermaker (Naval Auxiliary; 8,000 tons or over) | Purser (2,501-10,000 tons) Purser (Naval Auxiliary; up to 2,500 tons) Assistant Purser (Naval Auxiliary; 2,501-10,000 tons if only two pursers carried) Senior Assistant Purser (Naval Auxiliary; up to 2,500 tons) Junior Assistant Purser (Naval Auxiliary) Chief Steward (passenger ship over 10,000 tons or passenger ship 2,501-10,000 tons if no Purser carried) |
| Acting Sub-Lieutenant | Uncertificated Mate (Naval Auxiliary) | Uncertificated Engineer (Naval Auxiliary) Uncertificated Refrigerating Engineer (Naval Auxiliary) Chief (or only) Electrician (Naval Auxiliary; if only 1 or 2 electricians carried) Second Electrician (Naval Auxiliary; if up to 3 electricians carried) Electrician (Naval Auxiliary) Certificated Boilermaker (Naval Auxiliary; below 8,000 tons) | |
| Warrant Officer | Uncertificated Master (home trade cargo ship up to 500 tons) Uncertificated Mate (except home trade cargo ship up to 500 tons) Mate (home trade cargo ship 501–1,000 tons) Radio Officer or Wireless Telegraphist (1–3 years' service or Naval Auxiliary less than 3 years' service) Cable Foreman (cable ship) | Uncertificated Chief Engineer (home trade cargo ship up to 1,000 tons) Uncertificated Engineer (except home trade cargo ship up to 500 tons) Engineer (home trade cargo ship 501–1,000 tons) Senior Boilermaker Electrician (except cable ship) | Purser (up to 2,500 tons) Assistant Purser Chief Steward (passenger ship 2,501-10,000 tons if Purser also carried or passenger ship up to 2,500 tons or cable ship or Naval Auxiliary cargo ship over 10,000 tons) |
| Midshipman | Deck Apprentice or Cadet (Naval Auxiliary; 3 or more years' service) Radio Cadet (Naval Auxiliary; over 1 year's service) | Engineering Apprentice or Cadet (Naval Auxiliary; 3 or more years' service) |
| Cadet | Deck Apprentice or Cadet (Naval Auxiliary; less than 3 years' service) Radio Cadet (Naval Auxiliary; up to 1 year's service) | Engineering Apprentice or Cadet (Naval Auxiliary; less than 3 years' service) |
| Chief Petty Officer | Mate (home trade cargo ship up to 500 tons) Radio Officer or Wireless Telegraphist (less than 1 year's service) Deck Apprentice or Cadet Radio Cadet Boatswain Carpenter Plumber Cable Jointer (cable ship) Assistant Cable Foreman (cable ship) | Engineer (home trade cargo ship up to 500 tons) Boilermaker Uncertificated Boilermaker (Naval Auxiliary) Sanitary Engineer Engineering Apprentice or Cadet Chief Fireman or Stoker | Chief Steward (cargo ship) Chief Cook |
| Petty Officer | Boatswain's Mate Carpenter's Mate Chief Quartermaster Hospital Attendant | Donkeyman Pumpman Engineroom Storekeeper Engineroom Winchman First Leading Fireman Leading Hand Diesel Electrical Assistant | Baker Butcher Second Steward Senior Steward Saloon Steward Ship's Cook Officers' Cook First Writer Head Waiter Catering Storekeeper 1st Class |
| Leading Seaman | Craneman Lamp Trimmer Launchman Leading Seaman Painter Quartermaster Deck Storekeeper Deck Winchman Seaman Cable Jointer (cable ship) Cable Engine Driver (cable ship) | Greaser Leading Fireman or Stoker Assistant Engineroom Storekeeper | Second Cook (and Baker) Cook Catering Storekeeper Pantryman Leading Steward Second Writer |
| Able Seaman | Able Seaman Ordinary Seaman Seaman Cable Hand (cable ship) | Fireman or Stoker Trimmer Cleaner and Wiper | Assistant Catering Storekeeper Second Baker Assistant Baker Assistant Butcher Assistant Cook Assistant Pantryman Steward Assistant Steward Boy Steward |

## Footnotes

* ↑ Statutory Instrument 1949 No.1852 The War Pensions (Mercantile Marine) Scheme 1949 and Statutory Rules and Orders 1946 No.1640 War Pensions (Naval Auxiliary Personnel) Scheme