Glossary
DEERS
The Defense Enrollment Eligibility Reporting System — the record that decides whether you and your family are eligible for TRICARE, and the place to report changes in your life.
Applies to: All TRICARE plans · All regions
DEERS (the Defense Enrollment Eligibility Reporting System) is the Department of Defense registry of who is eligible for military benefits. TRICARE’s own guidance is direct about it: you must be registered in DEERS to receive your TRICARE benefit.
Who has to be registered
- Sponsors (service members) are registered automatically.
- Family members are not. The sponsor registers each eligible family member.
- If both parents are service members, one of them must be listed as the sponsor of each child.
Why it matters
TRICARE checks DEERS when you enroll in a plan and when your eligibility is verified. TRICARE asks beneficiaries to look at their DEERS information regularly and make sure the eligibility and enrollment details are correct. A missing family member or an out-of-date record is the most common reason a plan change or an enrollment stalls.
How to update DEERS
- Contact details (address, email, phone). Sponsors and registered family members can update these online through ID Card Online (“My Profile”) or milConnect, or by phone, fax, or mail to the DEERS Support Office.
- Adding or removing a family member. Only the sponsor can do this, in person at an ID card office. Many offices take appointments online, and TRICARE’s DEERS page links to the official ID card office locator.
- Social Security numbers. Sponsors make the change through their personnel office. A retired sponsor needs personnel office approval first, and the change then goes through DFAS. Family members update at an ID card office and should call ahead.
TRICARE’s rule of thumb is to update DEERS whenever something changes. Changes to your address or personal information also need to be reported to your TRICARE contractor; updating DEERS alone does not do it for you.
DEERS Support Office
As listed on TRICARE.mil: phone 800-538-9552 (TTY/TDD 866-363-2883); fax 800-336-4416 (alternate 502-335-9980); mail to DMDC/DEERS Support Office, Attn: COA, 400 Gigling Road, Seaside, CA 93955-6771. Use a physical address, not a P.O. box.
DEERS and life events
A qualifying life event such as a marriage, a birth, an adoption, a move, or retiring opens a 90-day period to change your TRICARE plan. TRICARE’s sequence is: update DEERS with the event first, then make your enrollment change, and pay any fees due inside the 90 days. TRICARE’s page for each life event has the specific steps: marriage, having a baby, divorce, moving, retiring, and deactivating.
Related questions
- How do I use milConnect?
- How do I update DEERS?
- How do I add a dependent to TRICARE?
- How do I enroll a newborn?
- What if I lose my TRICARE card?
- How do I check my TRICARE eligibility?
This page explains DEERS in general terms. For a problem with your own record, the DEERS Support Office and your nearest ID card office are the people who can see it.