Leslie Sosa graduated from Camas High School in Camas, WA in June of 2018. She originally signed an enlistment contract for combat service support in September of 2017 out of RSS Vancouver, WA. She earned the Naval Reserve Officer Training Corps Scholarship in May of 2018 while in the Delayed Entry Program; following her high-school graduation she attended The University of New Mexico where she majored in Political Science.
She attended Officer Candidates School in June and graduated in August of 2021, in May of 2021 she graduated and commissioned in Albuquerque, NM. Second Lieutenant Sosa attended The Basic School in October of 2021, she graduated in May of 2022 and was assigned to Combat Logistics Battalion-11, Combat Logistics Regiment-17. She attended Logistics Officer Course later that year in September until December. Following her graduation from LOC, she was assigned the Maintenance Management Officer (MMO) at CLB-11.
In February until May of 2023, Second Lieutenant Sosa attended SLTE 2-23, Weapons Tactics and Instructors Course as the Camp Commandant, S-4 and MMO. In May of 2023, Second Lieutenant Sosa was promoted to First Lieutenant. In June of 2023, 1stLt Sosa attended Joint Logistics Over the Shore Course. In July until September of 2023, First Lieutenant Sosa participated in Koa Moana as the executive officer for the Palau Detachment. In December of 2023, First Lieutenant Sosa was assigned a Distribution Platoon Commander, Alpha Company.
From January until March of 2024, First Lieutenant Sosa participated in SLTE 2-24/Integrated Training Exercise as a Distribution Platoon Commander. In June of 2025, First Lieutenant Sosa checked in to Inspector-Instructor duty Site Support New Haven, Connecticut. There she will oversee the site shutdown and provide training support to her reservists counterparts as well as Marines that are administratively controlled. These sites include fellowship students at Yale and pilots at Sikorsky.
In December of 2025, First Lieutenant Sosa was promoted to Captain.
Captain Sosas' personal awards include: the Navy and Marine Corps Achievement Medal w/gold star.