Jason M. Cantu enlisted in the delayed entry program in December 1992. He completed recruit training at MCRD San Diego, California on September 10, 1993. Following training at the School of Infantry, he was assigned the MOS 0331, machine gunner. 

In December 1993, Private First Class Cantu reported to Bravo Company, 1st Battalion, 2nd Marine Regiment, where he served as a machine gunner for Weapons Platoon. From September to December 1994, he participated in Operation SEA SIGNAL, fulfilling Haitian and Cuban migrant humanitarian missions while ashore at Guantanamo Bay, Cuba. In December 1995, Lance Corporal Cantu was temporarily assigned to SPMAGTF UNITAS/WATC for a deployment to South America and West Africa. In January 1996, Lance Corporal Cantu was reassigned to Bravo Company 1st Battalion, 2nd Marine Regiment, where he served as machinegun section leader for Weapons Platoon. In April 1997, the battalion deployed to the Mediterranean Sea as part of the 22nd MEU. During this tour, Lance Corporal Cantu was promoted to the ranks of Corporal, and Sergeant. In March 1998, Sergeant Cantu received orders to Weapons Training Battalion, Quantico, Virginia, where he served as an instructor at the Small Arms Weapons Instructors Corse (SAWIC). During this tour, Sergeant Cantu attended numerous marksmanship training courses sponsored by military and civilian law enforcement agencies. 

In September 2000, Sergeant Cantu again reported to 1st Battalion, 2d Marine Regiment. While assigned to 1/2, Sergeant Cantu served as a CAAT section leader in Weapons Company, as well as a platoon sergeant and platoon commander in Alpha Company. In June 2001 the battalion deployed to Okinawa, then Guam in support of Operation Enduring Freedom. Sergeant Cantu was promoted to Staff Sergeant in November 2001. In January 2003 the battalion deployed in support of Operation Iraqi Freedom. 

In September 2003, Staff Sergeant Cantu reported to Drill Instructor School at MCRD San Diego, California. He served in Drill Instructor, Senior Drill Instructor, and Chief Drill Instructor billets in Delta Company, 1st Recruit Training Battalion. In January 2005 Staff Sergeant Cantu was promoted to the rank of Gunnery Sergeant and temporarily assigned to the U.S. Naval Mission in Bogota, Colombia, where he was assigned as a Colombian Mobile Riverine Team Project SNCO. 

In December 2006, Gunnery Sergeant Cantu received orders to serve as an enlisted U.S. Marine Corps representative to the Chilean Marine Corps in Vina Del Mar, Chile, where he served as a tactics instructor at the Chilean Marine Corps School of Infantry. 

He was promoted to First Sergeant on September 1, 2008 and reported to 1st Intelligence Battalion in October 2008. In March of 2009 First Sergeant Cantu deployed in support of Operation Iraqi Freedom 9.1 as the CI/HUMINT Company First Sergeant. In March 2011, he reported for duty as the Inspector-Instructor First Sergeant for Beach and Terminal Operations Company B, 4th Landing Support Battalion, Bayamon, Puerto Rico.

Sergeant Major Cantu was frocked to his current rank in May 2013 and reported to 1st Battalion, 24th Marines, 25th Marine Regiment in Detroit, Michigan as the Inspector-Instructor Sergeant Major. In May 2015 Sergeant Major Cantu reported to HMH-465, MAG 16, 3d MAW. In May 2017 Sergeant Major Cantu received orders to Weapons Training Battalion, Quantico, Virginia. Sergeant Major assumed his current duties as the Site Sergeant Major for Marine Aircraft Group 41, 4th Marine Aircraft Wing, Naval Air Station, JRB Fort Worth in October of 2020. 

Sergeant Major Cantu’s awards include the Meritorious Service Medal (second award), Navy and Marine Corps Commendation Medal (fourth award) with Valor Device, the Navy and Marine Corps Achievement Medal (third award), and the Combat Action Ribbon.