What is DEERS? Military Database & TRICARE Eligibility | TRICARE.com

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## Definition DEERS (Defense Enrollment Eligibility Reporting System) is the mandatory global database that tracks military members and their families to determine who is eligible for TRICARE healthcare benefits and military ID cards.

## What it means in practice For a TRICARE beneficiary, DEERS is the "single source of truth." If your information in DEERS is incorrect or outdated, your medical claims will be denied, and you may be unable to fill prescriptions at the pharmacy. The database tracks your current address, your marital status, and the birth or adoption of children. Because TRICARE eligibility is tied directly to your status in this database, you must update DEERS immediately following any Qualifying Life Event (QLE), such as a move, marriage, or retirement.

In practice, keeping DEERS updated is the sponsor's responsibility. For example, if a service member gets married, they must visit a RAPIDS (Real-Time Automated Personnel Identification System) office with a marriage certificate to add their spouse. Only after the spouse appears in DEERS can they enroll in a specific plan like TRICARE Prime or TRICARE Select. In 2026, failing to update DEERS within 90 days of a QLE (or 120 days if stationed overseas) can result in a "lockout" period where you cannot change your enrollment until the next annual Open Season.

Accuracy in DEERS also affects your costs. For instance, whether you are classified as "Group A" (initial enlistment before Jan. 1, 2018) or "Group B" (initial enlistment on or after Jan. 1, 2018) is determined by your record in this system. This classification dictates whether you pay an annual enrollment fee for TRICARE Select and the specific dollar amounts for your 2026 copays and deductibles.

## Related terms * **Sponsor:** The active-duty, National Guard/Reserve, or retired service member through whom family members (dependents) gain TRICARE eligibility. * **Qualifying Life Event (QLE):** A major change, such as marriage or birth, that triggers a period where you can change your TRICARE enrollment outside of Open Season. * **MilConnect:** The web-based portal used by beneficiaries to manage their DEERS information and view healthcare eligibility. * **RAPIDS:** The physical office locations (Real-Time Automated Personnel Identification System) where beneficiaries go to update DEERS and get military ID cards. * **Beneficiary:** Any individual (sponsor or dependent) who is eligible for and receives TRICARE healthcare benefits.

## Sources * TRICARE.mil: [Defense Enrollment Eligibility Reporting System (DEERS)](https://www.tricare.mil/deers) * DMDC (Defense Manpower Data Center): [MilConnect Portal](https://milconnect.dmdc.osd.mil/) * Defense Health Agency: [Maintaining DEERS Information](https://health.mil)