TRICARE Regions: East vs. West & Overseas Guide

TRICARE is divided into two primary geographic regions in the United States—**East** and **West**—along with a third global region for those stationed or living **Overseas**. Each region is managed by a private contractor that handles claims, provider networks, and customer service for military families.

*Note: TRICARE.com is an independent reference site and is not affiliated with the Department of Defense. For official policy and enrollment, visit [TRICARE.mil](https://www.tricare.mil).*

## Quick answer The United States is split into two TRICARE regions: the East (managed by Humana Military) and the West (managed by TriWest Healthcare Alliance). Where you live determines which company processes your claims, manages your doctor network, and provides customer support. If you live outside the U.S., you fall under the TRICARE Overseas program managed by International SOS.

In detail

As of January 1, 2025, the TRICARE "T-5" contract went into effect, solidifying the current regional boundaries and contractor assignments. Understanding your region is critical because shifting from one to another (such as during a PCS move) requires an updated enrollment to ensure continuous coverage.

### TRICARE East Region The East Region covers 28 states plus the District of Columbia. It is currently managed by **Humana Military**. * **Coverage Area:** Alabama, Arkansas, Connecticut, Delaware, the District of Columbia, Florida, Georgia, Illinois, Indiana, 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 (only the eastern half), Vermont, Virginia, West Virginia, and Wisconsin.

### TRICARE West Region The West Region encompasses 26 states. Effective January 1, 2025, **TriWest Healthcare Alliance** took over operations from the previous contractor (Health Net Federal Services). * **Coverage Area:** Alaska, Arizona, California, Colorado, Hawaii, Idaho, Iowa, Kansas, Minnesota, Missouri (except the St. Louis area), Montana, Nebraska, Nevada, New Mexico, North Dakota, Oregon, South Dakota, Texas (western half, including El Paso), Utah, Washington, and Wyoming.

### TRICARE Overseas Program (TOP) For service members and families stationed abroad, TRICARE is managed as a single global region, partitioned into three sectors (Eurasia-Africa, Latin America/Canada, and Pacific). These are managed by **International SOS**.

Regional Contractor Comparison

*\*Note: The Catastrophic Cap is the maximum a family pays out-of-pocket per year. For 2026, the specific amount depends on your sponsor's status (Active Duty vs. Retired) and Group (A or B).*

## Who this applies to * **Active Duty Service Members (ADSMs):** Your region determines which Primary Care Manager (PCM) you are assigned to and which contractor coordinates your specialty care referrals. * **Active Duty Family Members (ADFMs):** If you are using TRICARE Prime or Select, your region determines your network of civilian providers. * **Retirees and their Families:** Your region impacts your monthly enrollment premiums (for Prime) and yearly enrollment fees (for Select Group A). * **TRICARE Reserve Select (TRS) / Retired Reserve (TRRR) Members:** You must pay your monthly premiums to the specific contractor for your region.

Common scenarios

### Scenario 1: A PCS Move from East to West An E-5 family moves from Fort Liberty, NC (East) to Fort Carson, CO (West) in June 2026. They must contact TriWest to "transfer enrollment." They do not need to wait for Open Season because a PCS is a Qualifying Life Event (QLE). Their 2026 deductible transfers with them, but they must choose a new PCM in the West Network.

### Scenario 2: Seeking Specialty Care A retired Navy Commander in Florida (East Region) needs a knee replacement. Because they are in the East, their doctor submits the authorization request to Humana Military. If they were visiting a doctor in California at the time of the injury, they would still need to coordinate through Humana Military since their home of record is in the East.

### Scenario 3: Living in a "Split" State A family lives in El Paso, Texas. Although much of Texas is in the East Region, El Paso is part of the West Region. They will pay their 2026 TRICARE Select enrollment fees to TriWest Healthcare Alliance rather than Humana Military.

## Related terms * **T-5 Contract:** The fifth generation of TRICARE contracts that reorganized West Region management in 2025. * **Contractor:** The private insurance company (Humana or TriWest) hired by the government to run the TRICARE network. * **Qualifying Life Event (QLE):** An event, like moving between regions, that allows you to change your TRICARE plan outside of Open Season. * **PCM (Primary Care Manager):** The specific doctor or clinic assigned to manage your care within your region. * **DEERS:** The global database (Defense Enrollment Eligibility Reporting System) that must be updated with your new address before you can switch regions.

## Sources * **TRICARE.mil Regions Page:** [https://www.tricare.mil/About/Regions](https://www.tricare.mil/About/Regions) * **Humana Military (East):** [https://www.humanamilitary.com/](https://www.humanamilitary.com/) * **TriWest Healthcare Alliance (West):** [https://www.triwest.com/](https://www.triwest.com/) * **TRICARE Overseas (International SOS):** [https://www.tricare-overseas.com/](https://www.tricare-overseas.com/)