TRICARE Turning 65: Medicare Transition Guide (2026) | TRICARE.com

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Turning 65 marks a mandatory shift in how your military health benefits function. To keep TRICARE coverage, you must enroll in Medicare Part B; at that point, your coverage automatically transitions from a Prime or Select plan to **TRICARE For Life (TFL)**, which acts as a wraparound supplement to Medicare.

## What changes When you turn 65, you shift from TRICARE’s managed care or PPO models (Prime/Select) to TRICARE For Life. Medicare becomes your primary payer for all covered services in the U.S. and U.S. territories, while TRICARE pays second. You lose the ability to use TRICARE Prime (unless you are an active duty family member) but you gain the freedom to see any provider that accepts Medicare, usually with zero out-of-pocket costs for covered services.

## What to do — checklist 1. **Verify your DEERS info:** Ensure your address and birthdate are correct in the Defense Enrollment Eligibility Reporting System (DEERS) via [milConnect](https://milconnect.dmdc.osd.mil/). **Deadline: 6–12 months before your 65th birthday.** 2. **Sign up for Medicare Part A:** Most people get Part A (hospital insurance) automatically based on work history. **Deadline: 3 months before your birthday.** 3. **Sign up for Medicare Part B:** This is **mandatory** to keep TRICARE. Sign up through the Social Security Administration. **Deadline: No later than 2 months before your 65th birthday** to ensure no gap in coverage. 4. **Confirm TFL Transition:** You do not need to "enroll" in TRICARE For Life. Once DEERS shows you have Part A and Part B, the system automatically transitions you. **Deadline: Effective your 65th birthday.** 5. **Notify your Doctors:** Inform your providers that Medicare is now your primary insurance and TRICARE is secondary. Provide them with your Medicare card and your MilID. **Deadline: Your first appointment after turning 65.** 6. **Review Pharmacy Options:** Your pharmacy benefit remains with Express Scripts, but you should verify if any specialty medications require new authorizations under the TFL transition. **Deadline: Within 30 days of turning 65.**

## Timeline | Timing | Action Required | | :--- | :--- | | **6 Months Prior** | Verify DEERS accuracy. Expect a notification letter from the Defense Health Agency (DHA). | | **3 Months Prior** | Initial Enrollment Period (IEP) for Medicare begins. Apply for Part A and Part B via Social Security. | | **1 Month Prior** | Receive your Medicare card. Ensure the Part B effective date matches your 65th birthday. | | **Day 0 (Birthday)** | TRICARE For Life becomes active automatically. Previous Prime/Select coverage ends. | | **90 Days Post** | Deadline for the "Qualifying Life Event" window if you need to make changes to dental/vision via FEDVIP. |

## Common pitfalls * **Declining Medicare Part B:** Some retirees believe they can keep TRICARE Select without Medicare. This is incorrect. If you do not have Part B, you lose all TRICARE eligibility (except for those on Active Duty). * **Missing the Enrollment Window:** If you miss your Initial Enrollment Period, you may have to wait for the General Enrollment Period (Jan 1–March 31), leading to a months-long gap where you have no TRICARE coverage and potentially higher Part B premiums for life. * **Purchasing a Medicare Supplement (Medigap):** TRICARE For Life *is* your supplement. Paying for a private Medigap plan is usually a waste of money because TFL already pays your Medicare deductibles and cost-shares. * **Ignoring the T-5 Contractor Change:** If you live in the West Region, ensure your records are updated with **TriWest Healthcare Alliance** (the contractor as of 2025/2026), though TFL claims are handled nationally by WPS Military Response.

## Sources * TRICARE For Life Official Page: [https://www.tricare.mil/tfl](https://www.tricare.mil/tfl) * Medicare & TRICARE (Social Security): [https://www.ssa.gov/medicare](https://www.ssa.gov/medicare) * TRICARE MilConnect (DEERS): [https://milconnect.dmdc.osd.mil/](https://milconnect.dmdc.osd.mil/)