TRICARE Regions Guide: East, West, and Overseas | TRICARE.com

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## Quick answer TRICARE manages its network through two geographic regions in the United States: **East** and **West**. As of 2026, Humana Military manages the East Region, and TriWest Healthcare Alliance manages the West Region. Your region determines your primary contractor, the network of civilian doctors you can see, and which customer service team handles your claims and referrals.

In detail

The TRICARE regional structure exists to provide a uniform health benefit while allowing regional contractors to manage local networks of civilian providers.

### The Two Domestic Regions Since January 1, 2025, under the T-5 contract, the United States has been divided into two specific regions:

1. **East Region:** Managed by **Humana Military**. Includes Alabama, Arkansas, Connecticut, Delaware, the District of Columbia, Florida, Georgia, Illinois, Indiana, Iowa (Rock Island area), Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri (St. Louis area), New Hampshire, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas (except El Paso area), Vermont, Virginia, West Virginia, and Wisconsin. 2. **West Region:** Managed by **TriWest Healthcare Alliance**. Includes Alaska, Arizona, California, Colorado, Hawaii, Idaho, Iowa (excluding Rock Island), Kansas, Minnesota, Missouri (excluding St. Louis), Montana, Nebraska, Nevada, New Mexico, North Dakota, Oregon, South Dakota, Texas (the El Paso area only), Utah, Washington, and Wyoming.

### Overseas Region Outside of the United States, all geographic areas fall under **TRICARE Overseas (TOP)**. * **Contractor:** International SOS. * **Areas:** Eurasia-Africa, Latin America and Canada, and the Pacific.

### Key Contractor Responsibilities Regardless of the region, your contractor (Humana, TriWest, or International SOS) is responsible for: * Establishing a network of civilian doctors, hospitals, and specialists. * Processing medical claims. * Approving authorizations and referrals for specialty care. * Providing customer service and a secure member portal. * Collecting enrollment fees (for plans like TRICARE Select or TRICARE Prime for retirees).

### Changing Regions When you move between regions (e.g., California to Virginia), your coverage does not automatically update its "home" region. You must: 1. Update your address in **DEERS** (Defense Enrollment Eligibility Reporting System). 2. Contact the new region's contractor to transfer your enrollment. 3. Choose a new Primary Care Manager (PCM) if you are in a Prime plan.

## Who this applies to * **Active Duty Service Members (ADSMs):** Must be enrolled in a specific region to ensure their PCM is correctly assigned and their "fitness for duty" care is tracked. * **Active Duty Family Members (ADFMs):** Region determines which network providers are available at "Network" copay rates (e.g., for TRICARE Select, the 2026 copay for a network primary care visit is $0 for Group A). * **Retirees and Families:** Region dictates where enrollment fees are paid. For 2026, TRICARE Select retiree enrollment fees are approximately $388.92/individual or $777.96/family per year for Group A. * **TRICARE Reserve Select (TRS) Members:** Region determines the contractor used for automated monthly premium payments ($53.80/month for individual or $274.48/month for family in 2026).

Common scenarios

**The Cross-Country Move** Sgt. Miller moves from San Diego, CA (West) to Fort Liberty, NC (East). In San Diego, his family used TriWest. Upon arriving in North Carolina, Sgt. Miller must update DEERS and then contact Humana Military to transfer their TRICARE Prime enrollment. If he fails to do this, his family’s medical claims in NC may be denied or processed as "out of network."

**The Snowbird Effect** A retired Navy Commander spends winters in Florida (East - Humana) and summers in Washington State (West - TriWest). Because his permanent address in DEERS is Florida, he is enrolled in the East Region. When in Washington, he must seek urgent care from TRICARE network providers to avoid high Point-of-Service fees, but his claims will still be processed by Humana Military.

**The El Paso Exception** A Soldier stationed at Fort Bliss in El Paso, Texas, is technically in the West Region (TriWest), even though the rest of Texas is in the East Region (Humana). If that Soldier travels to Dallas for specialty care, they are crossing into the East Region and must ensure TriWest has authorized the "out of region" care.

## Related terms * **T-5 Contract:** The 5th generation of TRICARE contracts which began full operations in 2025, naming TriWest as the West contractor. * **DEERS:** The database where all military sponsors and family members must keep their address updated to ensure regional eligibility. * **PCM (Primary Care Manager):** The specific doctor or clinic assigned to you within your region (Prime plans only). * **Point-of-Service (POS) Option:** An additional cost incurred when a TRICARE Prime member sees a doctor outside their regional network without a referral. * **Express Scripts:** The national pharmacy contractor that operates the same way regardless of your medical region.

## Sources * TRICARE.mil: TRICARE Regions (https://www.tricare.mil/About/Regions) * Humana Military (https://www.humanamilitary.com/) * TriWest Healthcare Alliance (https://www.triwest.com/) * TRICARE.mil: Moving (https://www.tricare.mil/LifeEvents/Moving)