TRICARE is a health program for:

Uniformed Service members and their families,
National Guard/Reserve membersIncludes members of the:
Army National Guard
Army Reserve
Navy Reserve
Marine Corps Reserve
Air National Guard
Air Force Reserve
U.S. Coast Guard Reserve
and their families,
Survivors,
Former spouses,
Medal of Honor recipients and their families, and
Others registered in the Defense Enrollment Eligibility Reporting System (DEERS).