What is TriWest? TRICARE West Region Contractor Guide | TRICARE.com

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## Definition TriWest Healthcare Alliance is the private insurance contractor responsible for managing the TRICARE West Region, serving as the primary point of contact for military families and veterans across 26 western states.

## What it means in practice As of Jan. 1, 2025, TriWest took over the TRICARE West Region contract (known as T-5). If you live in the West Region—which includes states like California, Texas (western parts), Washington, and Alaska—TriWest is your administrative partner. They do not provide the healthcare directly, but they manage the network of civilian doctors, process your medical claims, and handle your authorizations and referrals.

For a beneficiary, this means TriWest is where you go to find a doctor, check the status of a claim, or pay your enrollment fees. For example, if you are enrolled in TRICARE Prime and need a specialist, your Primary Care Manager (PCM) will submit a request to TriWest. TriWest then reviews the request and issues the formal authorization you need before your appointment. If you use TRICARE Select, you use TriWest’s online directory to ensure you are seeing a "Network" provider to keep your out-of-pocket costs lower.

While TRICARE sets the coverage rules and the 2026 rates (such as the $0 copay for active-duty members or specific 2026 copays for retirees), TriWest is the entity that actually cuts the check to your doctor. If you have a billing dispute or need to change your PCM, you log into the TriWest portal rather than a government website.

Your experience with TriWest is defined by your geographic location. If you move from the West Region to the East Region (managed by Humana Military), you must transfer your enrollment, as your medical records and authorizations do not automatically "follow" you between these two distinct private contractors.

## Related terms * **West Region:** The TRICARE geographic area consisting of 26 states managed by TriWest Healthcare Alliance. * **Humana Military:** The private contractor responsible for managing the TRICARE East Region. * **T-5 Contract:** The fifth generation of TRICARE managed care contracts which began full implementation in 2025. * **Network Provider:** A doctor or hospital that has a formal agreement with TriWest to provide care at pre-negotiated rates. * **Referral:** A request from your primary doctor that TriWest must approve before you can see a specialist under TRICARE Prime. * **Direct Care:** Healthcare services provided within a Military Treatment Facility (MTF) rather than through the TriWest civilian network.

## Sources * **TRICARE.mil:** [West Region Contractor Information](https://www.tricare.mil/west) * **TriWest Healthcare Alliance:** [Official Beneficiary Portal](https://www.triwest.com) * **Defense Health Agency:** [T-5 Contract Transition Updates](https://health.mil)