S
- SC: Cruiser Submarine (retired)
- SF: Fleet Submarine (retired)
- SM: Submarine Minelayer (retired)
- SP: Shore Patrol
- SS: Attack Submarine (Diesel-Electric Power)
- SSA: Auxiliary/Cargo Submarine (Diesel-Electric Power)
- SSAN: Auxiliary/Cargo Submarine (Nuclear Power)
- SSB: Ballistic Missile Submarine (Diesel Electric Power)
- SSBN: Ballistic Missile Submarine (Nuclear-Powered)
- SSC: Coastal Submarine (Diesel-Electric Power), over 150 tons
- SSG: Guided Missile Submarine (Diesel-Electric Power)
- SSGN: Guided Missile Submarine (Nuclear-Powered)
- SSI: Attack Submarine (Diesel Air-Independent Propulsion)
- SSK: Hunter-Killer/ASW Submarine (retired)
- SSM: Midget Submarine, under 150 tons
- SSN: Attack Submarine (Nuclear-Powered)
- SSO: Submarine Oiler (retired)
- SSP: Attack Submarine (Diesel Air-Independent Power) (alternate use), formerly Submarine Transport
- SSQ: Auxiliary Submarine, Communications (retired)
- SSQN: Auxiliary Submarine, Communications (Nuclear-Powered)(retired)
- SSR: Radar Picket Submarine (retired)
- SSRN: Radar Picket Submarine (Nuclear-Powered) (retired)
- SST: Training Submarine (Diesel-Electric Power)
Read more about this topic: List Of Hull Classifications