What is the Difference Between TRICARE East and TRICARE West?

Reviewed and updated July 21, 2026

QUICK ANSWER

What is the difference between TRICARE East and TRICARE West for rehab?

Your TRICARE region is generally based on where you live. Humana Military is the current East Region contractor, and TriWest Healthcare Alliance is the current West Region contractor. Provider networks, referrals, authorizations, and claims processes can differ. Use TRICARE’s ZIP-code region tool because some states have regional carveouts; regions do not apply to TRICARE For Life.

  • Confirm current eligibility and plan enrollment.
  • Check referral or pre-authorization rules for the requested service.
  • Verify provider authorization, network status, availability, and member costs.

Calls are answered by South Shores Recovery, a treatment provider. TriCareRehabs.com is an independent referral and helpline service and does not provide treatment. Coverage, costs, authorization, admission, and placement vary and are not guaranteed.

TRICARE East vs TRICARE West: A Side-by-Side Comparison

TRICARE is the health care program for uniformed service members, retirees, and their family members worldwide. The Department of Defense started using the name TRICARE in 1996, replacing CHAMPUS.

While TRICARE is comprehensive, it’s divided into regions to help manage care. If you’ve ever wondered about the difference between TRICARE East and TRICARE West, you are far from alone.

These regions are managed by different contractors and have unique features that impact access to care, provider networks, and customer service.

In this guide for TriCareRehabs.com, we’ll break down the key differences to help you understand which region you’re in and what you need to know about your benefits.

How Are the Various TRICARE Services Structured?

TRICARE East vs TRICARE West

Before we get into the regional differences, let’s start with what TRICARE is. TRICARE is a Department of Defense health agency for active duty service members, National Guard members, military members, retirees, and their families to receive medical care.

It offers various plans, including TRICARE Prime, TRICARE Select, TRICARE for Life, and more, each tailored to different needs. But depending on where you live, your healthcare coverage is under either TRICARE East or TRICARE West.

What is the TRICARE Regional Coverage Breakdown?

TRICARE is divided into two main regions in the US: the TRICARE East region and the TRICARE West region. This helps streamline administrative processes, provider networks, and customer support. Your region is determined by your physical address, not where you receive care.

  • TRICARE East covers states in the eastern half of the US (Alabama, Connecticut, Delaware, District of Columbia, Florida, Georgia, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia, Wisconsin).
  • TRICARE West covers states in the western half of the US (Alaska, Arizona, Arkansas, California, Colorado, Hawaii, Idaho, Illinois, Iowa, Kansas, Louisiana, Minnesota, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming)

Each region has a TRICARE contractor responsible for managing benefits, processing claims, and handling customer service inquiries. These contractors deliver essential support and resources to customers to ensure TRICARE is accessible and effective.

Formerly, TRICARE West states were managed by Health Net Federal Services as a contractor. As of January 1st, 2025, the states covered have been more clearly delineated, and TriWest Health Alliance now manages the TriWest region, with Humana Military continuing to administer the states covered by Tricare East. Note that if you or a loved one has received services from TriWest before January 1, 2025, you would still contact Health Net Federal Services for records and support if needed.


INDEPENDENT REFERRAL HELPLINE
Discuss TRICARE Treatment-Provider Options
855-720-0540

Calls are answered by South Shores Recovery, a treatment provider. TriCareRehabs.com does not provide treatment. Coverage, costs, authorization, admission, and placement vary and are not guaranteed.

How referrals work

What are the Main Differences Between TRICARE West and TRICARE East?

Core TRICARE benefit rules are generally national, while administration, provider networks, referrals, authorization, claims, and member costs can differ by region and plan. Both regions offer various types of care and providers, including network and non-network options. Below, we break down the differences.

Different TRICARE Regional Contractors: Humana Military vs TriWest Health Alliance

The biggest difference between TRICARE East and TRICARE West is the region contractor. The two regions and their assigned contractors are as follows:

  • TRICARE East is managed by Humana Military.
  • TRICARE West is now managed by TriWest Health Alliance, and was formerly managed by Health Net Federal Services (HNFS).

These contractors process claims, establish provider networks, and handle customer service. Depending on where you live, you’ll work with the corresponding contractor for all TRICARE issues.

A Shift in States Covered by TRICARE East vs TRICARE West (new for 2025)

States Covered Under TRICARE East and TRICARE West

Your region is determined by your home address, as stated above. This has been revised for clarity as of 2025, and Arkansas, Illinois, Louisiana, Oklahoma, Texas, and Wisconsin have all been administratively shifted to the TriCare West region.

Again, here is the updated breakdown of states in each region:

  • TRICARE East: Alabama, Connecticut, Delaware, District of Columbia, Florida, Georgia, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, Mississippi, Missouri, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, West Virginia, Wisconsin.
  • TRICARE West: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Kansas, Minnesota, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming.

The following states contain ‘carve-outs’ (areas where there is an alternative coverage provider, despite the state as a whole being covered by either East or West):

  • Arkansas: Clay, Craighead, Crittenden, Cross, Greene, Mississippi, Poinsett, St. Francis (those living in certain ZIP codes in these counties will stay in the East Region, while the rest of Arkansas shifts to West)

  • Indiana: Benton, Fountain, Lake, Vermillion, Warren (selected ZIP codes in those counties shift to the West Region; the rest of Indiana stays East)

  • Missouri: Butler, Dunklin, New Madrid, Pemiscot (selected ZIP codes in those counties remain in East, while the rest of Missouri moves to West)

  • Wisconsin: Florence (selected ZIP codes in Florence County will stay in East, while the rest of Wisconsin moves to West)

What are the Differences in TRICARE Provider Networks and Availability Nationwide?

Both TRICARE East and TRICARE West have large provider networks, but availability varies by location.

  • TRICARE East (Humana Military) has a larger provider network in the eastern US, including urban areas.
  • TRICARE West (formerly with Health Net Federal Services and now with TriWest) covers more rural and remote areas where provider availability may be more limited.

If you live in an area with fewer in-network providers, you may need referrals for specialty care or use TRICARE Select for more flexibility.

TRICARE East vs TRICARE West: Customer Service and Support

Call a TRICARE Rehabs Representative for Help

Each region has its own customer service contact information and online portal for beneficiaries. If you need treatment-provider options, call the independent TriCareRehabs.com referral helpline. Only TRICARE or its regional contractor can make a final benefits determination.

The Referral and Authorization Process: TRICARE West vs TRICARE East

TRICARE has standard policies, but the process for referrals and authorizations varies by region.

  • TRICARE Prime beneficiaries need referrals for specialty care. The regional contractor processes these referrals and assigns an in-network provider.
  • TRICARE Select beneficiaries do not need referrals but may have different cost-sharing for in-network or out-of-network providers.

Humana Military administers the East Region and TriWest Health Alliance administers the West Region; use the applicable official portal to check referral and authorization status.

How Do Claims Processing and Reimbursement Work for TRICARE East and West?

Each regional contractor processes claims separately.

  • TRICARE East Claims:
    • Claims are processed by Humana Military.
    • Electronic claims can be submitted on the Humana Military website.
  • TRICARE West Claims:
    • Claims are handled by TriWest Health Alliance (and formerly through Health Net Federal Services prior to 2025).
    • Claims can be submitted electronically through the TRICARE West portal.

If you receive care outside the TRICARE network, you may need to submit a claim for reimbursement. Follow your region’s submission process to avoid delays.

What Should TRICARE Holders Do About the TRICARE Region Changes in 2025?

As we broke down earlier, starting January 1, 2025, the TRICARE regional contractor for these states will be TriWest Healthcare Alliance.

TriWest Healthcare Alliance, a trusted healthcare alliance, will manage benefits, claims, and customer service for these states. Beneficiaries in these states should update their information in DEERS if they have not done so already to ensure a smooth transition and continuous access to care.

Understanding Health Care Options in TRICARE Regions

TRICARE Health Coverage Options

TRICARE has options for its beneficiaries based on their region. In the TRICARE East Region, managed by Humana Military, beneficiaries have access to a network of civilian providers, military psych hospitals, as well as military hospitals as a whole, and clinics.

In the TRICARE West Region, managed by TriWest Healthcare Alliance, beneficiaries can also access care through a network of civilian providers, military hospitals, and clinics.

To find a provider in your region, use the “Find a Doctor” tool on the TRICARE website. The “TRICARE Covered Services” tool lets you check if a specific service is covered under your plan. For those looking to compare costs, the “TRICARE Compare Costs” tool provides details on covered services, enrollment fees, and plan premiums.

Use official TRICARE tools for final benefit and provider-status information. The independent referral helpline can discuss treatment-provider options, but coverage, admission, and placement are not guaranteed.

Choosing the Right TRICARE Plan for Your Region

Core benefit categories may be similar across regions, but plan, provider, authorization, claims, and member-cost details must be verified for your region.

But factors like provider availability, customer service, and claims processing can impact your experience. When you move to another region, you must update your address in DEERS (Defense Enrollment Eligibility Reporting System) to ensure continuous coverage.


INDEPENDENT REFERRAL HELPLINE
Discuss TRICARE Treatment-Provider Options
855-720-0540

Calls are answered by South Shores Recovery, a treatment provider. TriCareRehabs.com does not provide treatment. Coverage, costs, authorization, admission, and placement vary and are not guaranteed.

How referrals work

Content reviewed and updated: July 21, 2026

Primary sources: TRICARE: Regions  •  TRICARE: East Region  •  TRICARE: West Region

Benefit, eligibility, regional, and provider requirements can change. Use official TRICARE channels for final eligibility, authorization, benefit, and cost information.

Get Support Today Using TriCare East or TriCare West

Understanding the difference between TRICARE East and TRICARE West can help you navigate your military benefits better. Core benefit categories may be similar, but contractors, provider networks, referrals, authorization, claims, and member costs can differ. Verify regional requirements before care.

If you have questions about your coverage, you can contact a TricareRehabs representative today. The referral helpline can discuss potential benefits and provider options, but only TRICARE or its contractor determines plan benefits.

Calls to the referral helpline are confidential. TriCareRehabs.com is not a treatment provider, and coverage, placement, and outcomes are not guaranteed.

Written and Reviewed by

  • Tim Edwards
    Compliance / Admissions & Insurance:

    Tim has extensive professional experience in the insurance field, which informs his understanding of coverage and access to care as our Admissions and Compliance reviewer.

  • Bryan Garman
    Writer/Author:

    Bryan Garman is a writer on behavioral health topics that speak to both the emotional and practical realities of substance use disorders.

Contact Our Sponsored Helpline

If you are seeking drug and alcohol related addiction rehab for yourself or a loved one, the TriCareRehabs.com helpline is a confidential and convenient solution.

Calls to any general hotline (non-facility) will be answered by South Shores Recovery.

To learn more about how TriCareRehabs.com operates, please contact us directly.

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