TRICARE For Life & Medicare: How It Works and Who Pays First

TRICARE For Life is the version of TRICARE that military retirees move to at 65, and it wraps around Medicare rather than replacing it. For most retirees it is enough coverage on its own: as long as you enroll in Medicare Part B and keep paying the premium, TRICARE For Life fills in around Medicare with no need to add Medigap or a Medicare Advantage plan.

What TRICARE For Life is

TRICARE For Life (TFL) is the TRICARE coverage that works with Medicare. When you reach Medicare eligibility, which is generally at age 65, your TRICARE coverage transitions to TFL automatically as long as you meet its requirements. TFL is designed to coordinate with Medicare, picking up where Medicare leaves off rather than standing in for it.1

This guide is specifically about TRICARE For Life. It is a separate program from Veterans Affairs (VA) health care, and the rules described here apply to TRICARE, not to VA coverage.

The defining feature of TFL is the requirement to carry Medicare alongside it. Once you are Medicare-eligible, TFL is secondary coverage that sits on top of Medicare, so Medicare has to be in place for the wraparound to function.

TRICARE For Life is not only for the retiree: eligible family members are covered under it too, and the same rule applies to each of them individually. As a spouse or other eligible family member reaches Medicare eligibility, keeping their TRICARE coverage depends on their own Medicare Part A and Part B. One person's Medicare enrollment does not cover another's, so each family member on Medicare has to carry Part B and keep paying its premium to stay covered.1

Why Part B is required to keep TRICARE

This is the rule that catches the most people off guard. To keep your TRICARE coverage once you become Medicare-eligible, you must have Medicare Part A and Part B. You will lose TRICARE coverage if you do not enroll in Part B, if you drop Part B, or if you fail to pay your Part B premiums. This applies even if you live overseas. You can confirm this on the TRICARE page on Medicare Part B premiums for TRICARE For Life.1

The reason is structural. TFL is built to be secondary to Medicare, so it assumes Medicare is paying first. Without Part B in place, there is no primary coverage for the outpatient and physician services Part B covers, and the wraparound cannot operate. Losing Part B means losing TRICARE along with it.

Because of this, timing your Medicare enrollment matters. For how Medicare enrollment windows work and how to avoid a gap, see Medicare enrollment periods. Enrolling in Part B when you are first eligible keeps your TRICARE coverage continuous.

How TRICARE For Life pays: Medicare first, TFL second

For care that both Medicare and TRICARE cover, Medicare is the primary payer and TFL is the secondary, or wraparound, payer. This is confirmed in the CMS guide to how Medicare coordinates with TRICARE.1

In most cases the process is automatic. The provider files the claim with Medicare, Medicare pays its share, and the claim then crosses over to the TFL claims processor. TRICARE pays the provider for TRICARE-covered services. For services that both Medicare and TRICARE cover, you often owe little or nothing out of pocket.1

The coordination is what makes TFL valuable. For care that both programs cover, Medicare handles the first layer of payment and TRICARE For Life then covers the Medicare deductibles and coinsurance that Medicare leaves behind, which is why most beneficiaries pay nothing out of pocket for that dual-covered care. Where a service is not covered by both, the wraparound does not apply, and standard TRICARE cost-shares (or, for care neither program covers, the full cost) fall to you instead.1

What TRICARE For Life costs you

The main out-of-pocket cost of TRICARE For Life is not a TFL premium, because TFL itself has no enrollment fee or monthly premium. The cost is the Medicare Part B premium you must keep paying to stay covered. In 2026, the standard Medicare Part B premium is $202.90 a month, and higher-income beneficiaries pay more through an income-related surcharge. Stop paying that premium and you lose Part B, and losing Part B ends your TRICARE coverage.2,1

TFL is also not a standalone plan and does not replace Medicare. It only wraps around Medicare, so for services Medicare does not cover, standard TRICARE rules and cost-shares apply instead of the low or no cost-sharing you get for dual-covered care. For a service neither program covers, you pay out of pocket.

If you are still working past 65

If you are still working at 65 and covered by an employer group health plan, Medicare's general rules let you delay Part B without a late penalty and use a Special Enrollment Period later, so long as that employer coverage is creditable. But TRICARE For Life is built to sit on top of Medicare, so once TFL is your coverage you still need Part A and Part B in place to keep it. If you are weighing whether to delay Part B while you work, confirm the timing before you skip it, because a wrong call can leave you without TRICARE. See Medicare enrollment periods for how the Special Enrollment Period works.3,1

Prescription drugs: you do not need Part D

The TRICARE pharmacy benefit is considered creditable prescription drug coverage. Because it is creditable, you do not need Medicare Part D to keep TRICARE, and you can decline Part D without a late-enrollment penalty as long as you keep your TRICARE pharmacy coverage.1

There is one thing to watch. If you went 63 or more continuous days without creditable drug coverage, you could face a Part D late-enrollment penalty later. As long as your TRICARE pharmacy coverage stays in place, that gap does not open. For more on how creditable coverage protects you, see Medicare creditable coverage. If you ever want to understand how Part D itself works, see Medicare Part D.4

Do you need Medigap or Medicare Advantage?

Generally, no. You do not need a Medigap policy or a Medicare Advantage plan with TFL, because TFL already wraps around Original Medicare. The role that a Medigap policy plays for other Medicare beneficiaries, filling in cost-sharing left by Original Medicare, is largely what TFL already does for you. For background on what Medigap is and who it serves, see Medicare and Medigap.1

The key requirement stays the same: keep Medicare Part A and Part B. That is what allows TFL to function as your wraparound coverage.

TRICARE For Life and Medicare at a glance

Where to get help

Learn More

If you are a military retiree mapping out how Medicare and TRICARE For Life will fit together, you can find clear, step-by-step guidance at brevy.com.

The information on Brevy.com is for educational purposes only and is not a substitute for professional legal, financial, or medical advice. Rules vary by state and program and change frequently. Always verify with the relevant agency or a qualified professional. Brevy is not a law firm, financial advisor, or healthcare provider.