TRICARE For Life is not a Medicare Supplement (Medigap) plan, but it functions like one. It’s a separate military retiree benefit that wraps around Medicare, picking up most costs that Medicare doesn’t cover. The practical result is similar to having a Medigap policy, often better, but the two are legally and structurally different programs.
How TFL Differs From Medigap
Medigap plans are private insurance policies sold by commercial insurers and regulated under federal standards. They come in lettered tiers (Plan G, Plan N, etc.), each with defined coverage levels and monthly premiums that typically range from $100 to $300 or more depending on your age, location, and the plan you choose.
TRICARE For Life is a federal entitlement earned through military service. It has no enrollment forms, no enrollment fees, and no separate premium. The only cost you pay is the standard Medicare Part B premium, which you’d owe regardless. Your TFL coverage begins automatically the first day you have both Medicare Parts A and B.
TRICARE itself describes TFL as “Medicare-wraparound coverage,” a term that signals it plays the same role as a supplement without being one. You can actually hold a private Medigap policy alongside TFL if you choose, though there’s rarely a financial reason to do so.
How Medicare and TFL Split Costs
When you receive a service covered by both Medicare and TRICARE, Medicare pays first as the primary insurer. TFL then pays second, covering the remaining deductibles and cost-shares. In most cases, you pay nothing out of pocket when a service is a benefit under both programs.
This is functionally identical to what the most generous Medigap plans do, with one key advantage: TFL also covers certain services that TRICARE includes but Medicare does not. For those services, TFL steps in as primary payer, and you pay only the standard TRICARE deductible and cost-share amounts.
If you have additional insurance through a current employer (yours or your spouse’s), that plan pays before TFL does. The payment order is always: Medicare first, then other health insurance, then TFL last.
Prescription Drug Coverage
One of the biggest practical differences between TFL and a private Medigap plan is pharmacy benefits. Medigap policies do not cover prescription drugs at all. You’d need a separate Medicare Part D plan for that.
TFL includes full prescription drug coverage through the TRICARE Pharmacy Program, and it qualifies as “creditable coverage,” meaning it pays at least as much as Medicare’s standard drug benefit. You don’t need to enroll in Part D. If you skip Part D and later decide you want it, your TRICARE pharmacy coverage protects you from the late enrollment penalty that other people face.
If you do carry both Part D and TFL for some reason, Medicare’s drug plan pays first and TRICARE pays last.
Overseas Coverage
This is another area where TFL outperforms any Medigap plan. Medicare does not cover healthcare outside the United States and its territories. Most Medigap plans offer limited foreign travel emergency coverage at best.
TFL continues to work overseas. When you receive care outside the U.S., TRICARE becomes the primary payer since Medicare has no role. You’re responsible for TRICARE’s annual deductible and cost-shares, but you still have meaningful coverage. If you live overseas permanently, you must maintain Part B enrollment to stay eligible for TRICARE, even though Medicare itself won’t pay for anything abroad.
Eligibility Requirements
TFL is available to anyone who is TRICARE-eligible and enrolled in both Medicare Part A and Part B, regardless of age or where you live. This typically includes military retirees, their spouses, and certain surviving family members. You do not need Medicare Part C (Medicare Advantage) or Part D.
The Part B requirement is non-negotiable. If you drop Part B, you lose TFL eligibility entirely. Some beneficiaries are surprised by this because Part B carries a monthly premium, and it can feel redundant when you already have military health benefits. But Part B is the price of admission: without it, the wraparound structure has nothing to wrap around.
What TFL Does Not Cover
Like any health plan, TFL has exclusions. Some notable gaps include long-term care, nursing home stays, assisted living, LASIK surgery, cosmetic procedures, acupuncture, massage, and exercise programs or gym memberships. Alternative treatments like naturopathic care, homeopathic remedies, and neurofeedback are also excluded.
Long-term care is the exclusion that catches people most off guard. Neither Medicare nor TRICARE covers extended nursing home stays or custodial care, so TFL’s wraparound design doesn’t help here. If long-term care is a concern, it requires separate planning outside both programs.
Why the Distinction Matters
Knowing that TFL is not technically a Medigap plan matters in a few practical situations. If a provider’s office asks whether you have a Medicare Supplement, the accurate answer is that you have TRICARE For Life, which functions as a wraparound but processes claims through the Defense Health Agency rather than a private insurer. Billing staff familiar with military benefits will know the difference.
It also matters when evaluating whether to buy additional coverage. Since TFL already fills the gaps that Medigap plans are designed to fill, and adds pharmacy and overseas benefits on top of that, purchasing a separate Medigap policy would be paying twice for nearly identical protection. For most TFL-eligible beneficiaries, the combination of Medicare Parts A and B plus TFL provides more comprehensive coverage than Medicare paired with even the best private supplement plan, at a lower total cost.