Sergeant Major Sean P. Cox is a native of Harvey, Illinois. He enlisted in the Marine Corps on 21 August 1990. Upon completion of recruit training at Marine Corps Recruit Depot San Diego, California, in November 1990, Private Cox was assigned to the School of Infantry West aboard Marine Corps Base, Camp Pendleton, California. He completed training with both Marine Combat Training Battalion and Infantry Training Battalion. Private First Class Cox was then assigned to Marine Corps Security Forces School at Mare Island, California. Upon Graduation from this school he was assigned to Marine Corps Security Forces Company Concord, California.
In April 1993, Lance Corporal Cox transferred to 1st Battalion, 1st Marines, Camp Pendleton, California. He completed one deployment on the 31st Marine Expeditionary Unit.
In December 1994, Corporal Cox was transferred to 1st Battalion, 7th Marines, 29 Palms, California where he performed the duties of Team Leader, Squad Leader and Platoon Sergeant. He completed two deployments to Okinawa, Japan in support of the Unit Deployment Program and graduated from the Summer Mountain Leaders Course at MCMWTC Bridgeport, CA.
In October 1998, Sergeant Cox received orders to Recruiter’s School. Upon completion of Recruiter’s School, he was assigned to Marine Corps Recruiting Station Chicago, Illinois. He served thirty months as a canvassing recruiter, six months as a Military Entry Processing Station Liaison representative and was meritoriously promoted to Staff Sergeant.
In January 2002, Staff Sergeant Cox was transferred to 1st Battalion, 5th Marines, Camp Pendleton, California where he served as a Platoon Sergeant and Platoon Commander. He deployed twice in support of Operation Iraqi Freedom (OIF).
In March 2005, Gunnery Sergeant Cox received orders to Marine Corps Security Guard School. Upon graduating from the course he was assigned to the United States Interest Section Havana, Cuba. In July 2006, he was reassigned to American Embassy Luxembourg, Luxembourg.
In July 2007, First Sergeant Cox reported to 2d Radio Battalion. He served as the Company First Sergeant in Company’s A, B and Headquarters and Service Company. He deployed once to Iraq in support of OIF with Company A.
In April 2010, First Sergeant Cox reported to 2d Battalion, 8th Marines. He was assigned to Company E and deployed with them to Sangin, Afghanistan from January to August 2011.
Sergeant Major Cox received orders to Recruiting Station Twin Cities, Minnesota, in February 2012. After a successful tour on recruiting duty he received orders to HMLA 367 aboard Marine Corps Base Kaneohe Bay, Hawaii in January 2015.
Sergeant Major Cox completed a successful tour with HMLA 367 in August 2016. He then reported to Marine Aircraft Group 24 (MAG 24), 1st Marine Aircraft Wing for duty as the MAG 24 Sergeant Major.
Sergeant Major Cox executed orders to his current duty station at Marine Helicopter Squadron-1 in March 2018.
Sergeant Major Cox's personal decorations include: the Meritorious Service Medal with one gold star, Navy and Marine Corps Commendation Medal with two gold stars and the combat distinguishing device, Navy and Marine Corps Achievement Medal with three gold stars and the combat distinguishing device and the Combat Action Ribbon with one gold star.