Regions
TRICARE is managed in three separate regions: the East Region, the West Region, and the Overseas Region.
Your region is based on where you live.
- I live in one of the 50 United States or the District of Columbia: It’s easy to find your region. Go to the “What TRICARE region am I in?” tool on this page and enter your ZIP code. Or view a list of states in each region.
- I live in a U.S. territory or another overseas location: You live in the Overseas Region.
Each region has its own regional contractor.
- Regional contractors provide health care services and support for most TRICARE health plan options.
- Other contractor partners provide health care services and support for TRICARE For Life (in the U.S. and U.S. territories), the US Family Health Plan, and the TRICARE Prime Demo.
- Additionally, there are contractor partners to provide support for TRICARE pharmacy and dental benefits.
TRICARE Stateside Regions
| East Region Contractor | West Region Contractor |
|---|---|
|
Humana Military 800-444-5445 TRICARE East Region website |
TriWest Healthcare Alliance 888-TRIWEST (874-9378) TRICARE West Region website |

TRICARE Overseas Region
The Overseas Region includes the U.S. territories and all other overseas locations. International SOS is the contractor for the Overseas Region.
The Overseas Region is divided into three areas. Each area has different contact information.
| Eurasia-Africa Area | Latin America and Canada Area | Pacific Area |
|---|---|---|
| +44-20-8762-8384 (overseas) 877-678-1207 (stateside) |
+1-215-942-8393 (overseas) 877-451-8659 (stateside) |
+65-6339-2676 (overseas) 877-678-1208 (stateside) |
Find country-specific phone numbers on the International SOS TRICARE Overseas website.
Last Updated 1/2/2026