LtCol Howarth entered the Marine Corps Delayed Enlistment Program in June of 1999 and shipped to MCRD Parris Island for recruit training, followed by the School of Infantry aboard Camp Geiger, NC. PFC Howarth’s first unit was Company L, 3rd Bn, 25th Marines were he served as a rifleman and SAW gunner.
In 2004 Corporal Howarth deployed as part of a SMAGTF to South America for an iteration of UNITAS. He served as in infantry team leader throughout the deployment. During this time, he completed his Bachelors’ Degree from The Ohio State University.
In February of 2005 Corporal Howarth passed an indoc for the Scout Sniper Platoon and immediately deployed to Iraq with 3rd Bn 25th Marines in support of Operation Iraqi Freedom. There he served in the billets of sniper team radio operator, assistant team leader and team leader. He served in Al Anbar Iraq in Hit, Haditha, and Al Kiem supporting ground units of Regimental Combat Team 7.
In January of 2009 Staff Sergeant Howarth reported to Officer Candidate School and graduated in March as a 2nd Lieutenant. He reported to The Basic School in March and to the Infantry Officer Course in October of the same year graduating in December of 2009 as an 0302.
In January of 2010 he reported to Lima Company 3/25 as a platoon commander and began a work up for deployment to Afghanistan. He deployed to Afghanistan in August of 2010 in support of OEF 10.2. There he served as an infantry platoon commander in Helmand Province.
Upon returning from Afghanistan Lt Howarth transferred to Co E, 4th Recon Bn in January 2012. There he held the billets of platoon commander and operations liaison officer. In October of 2018 Captain Howarth deployed to Okinawa Japan in support of UDP 19.1.
In 2020 Maj Howarth assumed the duties of Operations Officer at 3d Force Reconnaissance Company and served through 2024. In September 2024, he took over as the Executive Officer and served there until he assumed command of 4th Reconnaissance Battalion in April of 2026.