Glossary
Medicare Assignment
A provider's agreement to accept Medicare's approved amount as full payment.
Also known as: accepts assignment, Medicare-participating provider
What is it?
When a provider 'accepts assignment,' they agree to charge no more than the Medicare-approved amount for covered services. Most doctors are participating providers (they always accept assignment). Some are non-participating (may charge up to 15% above the approved amount).
Why does it matter?
TFL covers Medicare cost-shares only at Medicare-participating or non-opt-out providers. If a doctor has opted out of Medicare entirely, TFL pays nothing and you owe the full bill.
When you'll encounter it
Every time you choose a new doctor. Verify at Medicare.gov Care Compare or by asking the office directly.
Impact on Medicare
Determines what Medicare pays and what you're responsible for.
Impact on TRICARE For Life
TFL only fills the cost-share gap if Medicare paid. No Medicare = no TFL secondary payment.
Common misconceptions
- "All doctors take Medicare." — Most do, but some specialists (especially psychiatrists and concierge doctors) have opted out entirely.
Related lessons
Related questions
Official sources
Last reviewed January 2026 against the 2026 Medicare & You and TRICARE For Life handbooks.