Captain Reilly D. Treat is a native of Yakima, Washington. She graduated from Emerald Ridge High School in 2016 and reported to the United States Naval Academy, Annapolis, Maryland on July 1, 2016 for Plebe Summer. While at the academy, Midshipman Treat earned a Bachelor of Science in Arabic and studied abroad in Meknes, Morocco. After graduation and commissioning on May 22, 2020, Second Lieutenant Treat worked with the Marine Corps Detachment at the Naval Academy and reported to The Basic School on September 1, 2020. Upon graduation of The Basic School, Second Lieutenant Treat reported to the Marine Artillery Officer Basic Course, Fort Sill, Oklahoma in April of 2021.
Upon completion of MOS training, Second Lieutenant Treat executed orders to Battery A, 1st Battalion, 11th Marines aboard Camp Pendleton, California in September, 2021. She served as the Headquarters Platoon Commander and Fire Direction Officer. She was promoted to the rank of First Lieutenant in May of 2022. She deployed with Battalion Landing Team 2/4 in support of the 13th Marine Expeditionary Unit and the Western Pacific Patrol 23.1 on the USS JOHN P. MURTHA from November 2022 through June 2023. Upon return from deployment, First Lieutenant Treat assumed the role as Battery A's Executive Officer. She served with the battery until its deactivation on November 28, 2023.
In May 2024, Captain Treat executed orders to Battery Q, 5th Battalion, 14th Marine Regiment, aboard Air Force Base Buckley, Colorado where she currently serves as the Inspector-Instructor.