| Rank[navcomnote 2] | Crewman Recruit (CR) | Crewman Apprentice (CA) | Crewman (CR)[navcomnote 3] | Petty Officer Third Class (PO3) | Petty Officer Second Class (PO2) | Petty Officer First Class (PO1) | Chief Petty Officer (CPO) | Senior Chief Petty Officer (SCPO) | Master Chief Petty Officer[navcomnote 4] (MCPO) |
| Typical responsibilities | Boot camp and training school | Initial fleet assignment | Work crew | Work party lead | Compartment supervisor | Work division supervisor | Deck supervisor | Oversight of ship enlisted personnel | Fleet administration or HIGHCOM staff |
| Rank code | OT | WO-1 | WO-2 | O-1 | O-2 | O-3 | O-4 | O-5 | O-6 | O-7 | O-8 | O-9 | O-10 |
| Rank | Cadet (CDT) | Warrant Officer (WO) | Chief Warrant Officer (WO-2) | Ensign (ENS) | Lieutenant Junior Grade (LTJG) | Lieutenant (LT) | Lieutenant Commander (LCDR) | Commander (CDR) | Captain (CAPT) | Rear Admiral (RADM) | Vice Admiral (VADM) | Admiral (ADM) | Fleet Admiral (FADM) |
| Typical responsibilities | No command authority | Resident technical expert | Command advisor or captain of utility ship | Initial officer posting | Command of staff section | Command of work division or Captain of support ship | First officer on small warship or command of ship department | HIGHCOM staff or captain of small warship[navcomnote 5] | Captain of line warship or installation[navcomnote 6] | Battle group commander | Command of Sector fleet or academy | HIGHCOM staff | Fleet commander |
Notes
- ^ Rank codes are not provided for enlisted Naval personnel in Halo: Official Spartan Field Manual. While it is likely they use the same "E-1, E-2" etc. system as other rank codes, they are omitted from this table as to only display confirmed information.
- ^ The "CR" abbreviation is also used for Crewman Recruit in the Halo: Official Spartan Field Manual. In real life Crewman uses the abbreviation "CN", leading to it likely a typo for Crewman to use this. CR is however used here due to it appearing in one source.
- ^ Although Master Chief Petty Officer is the official rank held by many naval servicemen, they are typically referred to as "Top Chief" by crew out of respect for John-117, more commonly known as "The Master Chief".
- ^ Commanders have also been shown to command small fleets and battle groups, an example being Commander Miranda Keyes commanding Seventh Fleet and Commander Lasky commanding Battle Group Dakota.
- ^ Captains have also been shown to command entire fleets and battle groups, an example being Captains Del Rio and Lasky commanding Expeditionary Strike Group 1 Fleet and Captain Veredi commanding Battle Group 4.