Medicare 2026

TRICARE For Life and Medicare Part B: Why Military Retirees Need to Enroll at 65

If you have TRICARE and you're approaching 65, there's one Medicare decision that matters more than any other: signing up for Part B. TRICARE For Life (TFL) is designed to work with Medicare, not instead of it. Miss the Part B step, and you can lose TRICARE coverage on the day you were counting on it most.

Here's a plain-language walk through how the two programs fit together, who must enroll, and when.

How TRICARE For Life actually works

TRICARE For Life is "wraparound" coverage. Once you have both Part A and Part B, TFL kicks in automatically — there's nothing to sign up for and no premium to pay to TRICARE itself.

For a service covered by both Medicare and TRICARE, Medicare pays first and TRICARE picks up the remaining amount. In most cases, you pay nothing out of pocket for that service.

For a service only Medicare covers, you pay the normal Medicare deductible and cost-share. For a service only TRICARE covers, you pay the TRICARE deductible and cost-share. When TRICARE is the only payer, the 2026 TRICARE deductible is $150 per individual or $300 per family, and the TRICARE catastrophic cap on out-of-pocket costs is $3,000 per family for the calendar year.

Who must have Part B to keep TRICARE

If you're eligible for premium-free Part A, TRICARE requires Part B to stay eligible. That applies to:

• Retired service members, including retired National Guard and Reserve members drawing retirement pay
• Family members of retired service members
• Medal of Honor recipients and eligible family members
• Survivors of deceased sponsors
• Eligible former spouses

The one group with a different path: if you are not eligible for premium-free Part A at 65 on your own or a spouse's record (including a divorced or deceased spouse), you do not need Part B to keep TRICARE. You take Social Security's Notice of Award or Notice of Disapproved Claim to a Uniformed Services ID card office to maintain TRICARE Prime or TRICARE Select eligibility. TRICARE still advises anyone who expects to qualify later on a spouse's record to enroll in Part B during their Initial Enrollment Period, so there's no late penalty down the road.

The timing that prevents a gap

The TRICARE For Life Handbook (updated August 2026) is specific: to avoid a break in coverage, enroll in Part B no later than one month before the month you turn 65 — or two months before, if your birthday falls on the first of the month.

TFL coverage begins automatically on the first day both Part A and Part B are active. If Part B starts late, TFL starts late.

What if you're still working at 65?

Even if you have employer-sponsored coverage through your or your spouse's current job, TRICARE's handbook says you still need Part B to remain TRICARE-eligible if you qualify for premium-free Part A.

If you do delay Part B and rely only on employer coverage from current work, you can sign up later using Medicare's employer-coverage Special Enrollment Period, which waives the Part B late penalty. TRICARE's guidance is to enroll in Part B before retiring or losing that employer coverage, so TFL begins the moment the employer plan ends.

The cost of Part B

The Part B premium is yours to pay — TFL does not cover it. For 2026, the standard Part B premium is $202.90 per month, and the Part B deductible is $283. Higher-income beneficiaries pay more. The 2027 Part B premium, deductible, and the income-related (IRMAA) brackets have not yet been announced; CMS typically announces those figures in the fall. Check Medicare.gov once they're published.

Social Security has announced a 3.6 percent cost-of-living adjustment to benefits payable beginning January 2027, which may affect what shows up in your deposit after any Part B premium is withheld.

What about Part D and TRICARE pharmacy?

TRICARE includes its own prescription drug benefit, and TRICARE pharmacy coverage is considered creditable, meaning it's at least as good as Medicare Part D. Many TFL beneficiaries keep TRICARE pharmacy and don't enroll in a separate Part D plan. If you ever consider Part D, know that in 2027 the annual out-of-pocket cap for covered Part D drugs will be $2,400 (it's $2,100 in 2026), and no Part D plan may charge a deductible higher than $700.

A note on Medicare Advantage vs. Original Medicare

Some people with TRICARE wonder whether to join a Medicare Advantage plan. Both paths have trade-offs. Original Medicare paired with TFL gives you broad provider access and the familiar wraparound structure described above. A Medicare Advantage plan replaces how Original Medicare pays claims, which can change how TFL coordinates. This is an individual decision, not a one-size-fits-all answer. Review your options carefully before making a change.

Help with costs

People with Medicaid or Extra Help have a monthly Special Enrollment Period to move to Original Medicare with a stand-alone Part D plan, or to switch stand-alone Part D plans. Full-benefit dual-eligible individuals can join an integrated D-SNP in any month.

Where to go next

For official Medicare enrollment windows, forms, and the Part B figures once CMS announces them, visit Medicare.gov or call 1-800-MEDICARE (1-800-633-4227), available 24/7. For TRICARE-specific questions, the TRICARE For Life Handbook is the authoritative reference.

The bottom line: if you qualify for premium-free Part A and you want TRICARE to continue past 65, enroll in Part B on time. Everything else about TFL happens automatically.