A native of Fullerton, CA, SgtMaj Alfaro enlisted in the Marine Corps and attended Recruit Training at Marine Corps Recruit Depot, San Diego in October 1995. Upon completion of recruit training and Marine Combat Training Private First Class Alfaro reported to Military Police School, Ft. McClellan, AL where he obtained the Military Occupational Specialty of 5811. He completed the school as the honor graduate and was meritoriously promoted to the rank of Lance Corporal.
In June 1996, LCpl Alfaro transferred to the Select Marine Corps Reserve and reported to Marine Wing Support Squadron (MWSS) 473, Marine Corps Air Station (MCAS) El Toro, CA. In August 1996, LCpl Alfaro's unit was relocated to MCAS Miramar, where he continued to serve and was later promoted to the rank of Corporal and Sergeant while filling the billets of squad leader and patrol supervisor.
In April 2002, Sgt Alfaro augmented to Active Duty and was assigned to the Provost Marshal's Office (PMO) MCAS Miramar. While assigned at PMO Sgt Alfaro served as a squad leader and was a member of the Special Reaction Team.
In December 2003, Sgt Alfaro received orders to PMO, Marine Corps Base (MCB) Camp Pendleton. While Assigned to PMO, Sgt Alfaro served as a squad leader and patrol supervisor. In April 2006, he was promoted to the rank of Staff Sergeant, and served as the Staff Non-Commissioned Officer in Charge (SNCOIC) of the Dispatch and Services section.
In October 2006, SSgt Alfaro volunteered to return to MCRD San Diego for Drill Instructor Duty. While there he served as a Drill Instructor, Experienced Drill Instructor, Senior Drill Instructor, Series Chief Drill Instructor and Marine Combat Instructor Water Survival.
In December 2009, SSgt Alfaro reported again to PMO, MCB Camp Pendleton. In April 2010, SSgt Alfaro deployed to Afghanistan on an individual augmentation billet as a Physical Security and Force Protection SNCOIC for the Army Corps of Engineers, Afghanistan District South. Upon completion of the deployment, SSgt Alfaro returned to PMO and served as a Platoon Sergeant. In August 2011, SSgt Alfaro was promoted to the rank of Gunnery Sergeant.
In June 2012, GySgt Alfaro was transferred to Military Police Instruction Company (MPIC), Marine Corps Detachment Ft. Leonard Wood, MO. While assigned to MPIC, GySgt Alfaro served as the Company Gunnery Sergeant, Senior Instructor, and an Instruction Phase Chief.
In April 2014, GySgt Alfaro was selected to serve at Officer Candidates School, MCB Quantico. While there he served as a Sergeant Instructor, and was later promoted to the rank of First Sergeant. After promotion, he served as the Company 1stSgt for Charlie Company, Lima Company, and Headquarters and Service Company.
In May 2017, 1stSgt Alfaro transferred to Okinawa, Japan, and reported to 3d Reconnaissance Battalion, where he served as the Company 1stSgt for Bravo Company. While serving there he was selected and then frocked to his current rank. In January 2019, SgtMaj Alfaro was assigned to Combat Logistics Battalion 31 to serve as the Battalion SgtMaj. During his tour, SgtMaj Alfaro participated in three deployments with the 31st Marine Expeditionary Unit.
In June 2020, SgtMaj Alfaro reported to MCRD Parris Island and assumed the Duties of Battalion SgtMaj for First Recruit Training Battalion. In May 2021, he was reassigned to Support Battalion where he served until receiving orders to MCAS Beaufort to serve as the station SgtMaj.
SgtMaj Alfaro's personal awards include the Bronze Star Medal, Meritorious Service Medal with one gold star, Navy and Marine Corps Commendation Medal with three gold stars, and the Navy and Marine Corps Achievement Medal with one gold star.