Tricare Service Center is located inside the hospital along Hospital Road near Challenger Drive.
The business offers veterans help with questions on disability benefits and other paper work.
The Department of Defense decided to end operations by mid-February because of a transition between service contracts with health care companies.
The move forces veterans to drive 90 miles to Lemoore or 150 miles to Beale Air Force Base to receive in-person assistance.
In the past six months, more than 300 walk-in visitors used the service center, in addition to assistance over the phone.
The medical group at the 144th Fighter Wing in Fresno also uses the facility.