Glossary
Secondary Payer
The insurance plan that pays after the primary plan, covering remaining eligible cost-shares.
Also known as: payer of second resort
Quick answer
The secondary payer receives the claim after the primary payer has finished. It reviews what's left (deductibles, coinsurance, copays) and pays according to its own rules. For most TFL beneficiaries, TFL is the secondary payer behind Medicare.
Why it matters
Understanding TFL's secondary-payer role explains why your share of most U.S. medical bills is $0 — and why some bills legitimately take 6–8 weeks to fully resolve.
Why this matters at age 65
TFL's entire value proposition is rooted in being the right secondary payer behind Medicare. If Medicare doesn't pay (opt-out provider, non-covered service), TFL's secondary role disappears.
When you'll encounter it
After every Medicare claim — the Medicare MSN arrives first, then the TFL EOB from WPS follows.
Impact on Medicare
Does not change how Medicare pays.
Impact on TRICARE For Life
TFL's secondary-payer role is the heart of the TFL benefit. It typically reduces the Medicare 20% coinsurance and Part B deductible to $0 on services covered by both programs.
Impact on Medicare Advantage
TFL is also secondary behind an MA plan, helping cover plan copays and coinsurance for TRICARE-covered services.
Common misconceptions
- "If Medicare denies a claim, TFL won't pay either." — Not always. If the service is TRICARE-covered but not Medicare-covered, TFL may pay AS PRIMARY up to TRICARE limits.
- "TFL pays everything Medicare doesn't." — Only services covered by both programs. Cosmetic surgery, most dental, and routine hearing care are excluded by both.
Common mistakes to avoid
- Paying a bill the day it arrives without confirming TFL has finished processing.
- Assuming TFL will pay for a service Medicare denied for medical-necessity reasons (it usually won't).
Real-world scenario: A retiree gets an MRI. Medicare approves $1,200 and pays $960 after deductible.
Medicare leaves $240 + the unmet $240 Part B deductible. TFL, as secondary, pays both — patient owes $0. The TFL EOB arrives about 2 weeks after the MSN.
What should I do?
- 1Wait for both the Medicare MSN and the TFL EOB before paying any provider invoice.
- 2If a balance remains after TFL paid, double-check the provider accepts assignment — and call WPS if numbers don't match.
- 3For TRICARE-only covered services, ask the provider to file with WPS as primary.
Questions people commonly ask
Continue learning
— suggested by the knowledge graph- How Medicare and TRICARE For Life work togetherThe exact mechanics of who pays first, who pays second, and what you owe — for every common care scenario.
- How Medicare and TRICARE For Life claims are paidThe mechanics of the Medicare-to-TFL crossover system — what providers do, what WPS does, and what to do if a claim gets stuck.
- Understanding Original Medicare (Parts A & B) for veteransExactly what Part A and Part B cover, what they cost in 2026, and why both are required to keep TRICARE For Life.
- Enrolling in Medicare: timing, methods, and the military-specific rulesWhen and how to sign up for Medicare Parts A and B — and the timing that protects your TRICARE For Life activation.
- Balance BillingThe practice of a provider billing you for the difference between their charge and what insurance approved.
- Billing ErrorsMistakes — accidental or intentional — on Medicare or TFL claims, ranging from duplicate charges to outright fraud.
- ClaimA formal request to an insurer for payment of a covered service.
- Explanation of Benefits (EOB)A statement from your insurer showing what a provider billed, what the plan paid, and what you may owe.
- Medicare AssignmentA provider's agreement to accept Medicare's approved amount as full payment for a covered service.
- Medicare Summary Notice (MSN)Medicare's quarterly statement listing every Part A and Part B claim processed for you — Medicare's version of an EOB.
- What is a Medicare Summary Notice (MSN)?A quarterly summary from Medicare listing every claim filed under your number — what Medicare approved, paid, and what you may owe. Compare it against your WPS TFL EOBs.
- Who pays first, Medicare or TRICARE For Life?Medicare pays first for any service it covers. TFL pays second. The claim usually crosses over automatically — you should never pay out of pocket up front.
- How much does Medicare Part B cost?Most people pay the standard Part B premium (roughly $185/month in 2026). Higher-income retirees pay IRMAA on top. Lower-income retirees may qualify for help paying it.
- I have other insurance besides Medicare and TFL. Who pays first?Order varies. Active-employment group insurance pays before Medicare; retiree coverage like FEHB pays after Medicare and usually before TFL. TFL is almost always last.
- What do I do if my Medicare claim is denied?Read the MSN denial reason, gather supporting records, and file a Redetermination with the Medicare Administrative Contractor within 120 days.
Related glossary terms
Related Official Resources
Continue learning straight from the source. Every link below goes to an official government or DoD resource.
Last reviewed January 2026 against the 2026 Medicare & You and TRICARE For Life handbooks.