Note: the shown insignia is for the Army's E-2 Private rank. The Army's E-1 Private rank, as well as the Marine Private rank, have no insigna. Private Affiliation UNSC Marine Corps and UNSC Army Higher Rank Private First Class Lower Rank None Command None Known Privates Bisenti Cochran Fincher Tom Gerencer Kappus McKenzie Manuel Mendoza Wallace A. Jenkins O'Brien Marie Postly Riley Rodriquez Satha SPARTAN-G099 Walker

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Private is the lowest enlisted rank of the UNSC Marine Corps, and the two lowest in the UNSC Army. The Marine Corps Private (Pvt) and the lower Army Private (PV1) are of the grade E-1 and are equal in rank to Crewman Recruit in the UNSC Navy and Airman Basic in the Air Force. The Army's higher Private (PV2) is of the E-2 grade, and is equal to PFC in the Marines, Crewman Apprentice in the Navy, and Airman in the Air Force. For most recruits into the Marine Corps and Army, upon completing basic training, they become a Private, and are further assigned to a specific unit. Private First Class is the next higher rank.

UNSC Defense Force enlisted ranks
	E-1	E-2	E-3	E-4	E-5	E-6	E-7	E-8	E-9	Senior Enlisted Advisor
Air Force:	AB	Amn	A1C	SrA	SSgt	TSgt	MSgt	SMSgt	CMSgt - CCM	CMSAF
Army:	PV1	PV2	PFC	SPC - CPL	SGT	SSG	SFC	MSG - 1SG	SGM - CSM	SMA
Marine Corps:	Pvt	PFC	LCpl	Cpl	Sgt	SSgt	GySgt	MSgt - 1stSgt	MGySgt - SgtMaj	SgtMajMC
Navy:	CR	CA	CN	PO3	PO2	PO1	CPO	SCPO	MCPO - CMDCM - FORCM - FLTCM	MCPON