What does it mean if your doctor doesn’t accept assignment?

What does it mean if your doctor doesn’t accept assignment?

If your doctor doesn’t “accept assignment,” (meaning they’re a non-participating provider), they might see Medicare patients and accept Medicare reimbursement as partial payment, but they might not accept Medicare’s approved reimbursement amount as the full payment for their services.

The provider can choose to accept Medicare’s approved rates as payment in full on a case-by-case basis, but not across the board. This could mean that you end up paying for for their services than you’d pay if your doctor accepted assignment.

How much will I pay if my doctor doesn't accept assignment?

If you have Medicare and you see a doctor who doesn’t accept assignment, you may end up paying the difference between what Medicare will pay and what your provider charges. This can be up to 15% above the amount that participating providers are paid by Medicare, and you’ll pay the extra fee in addition to your normal deductible and coinsurance.

This additional 15% is known as a limiting charge. States can impose a lower threshold, but it cannot exceed 15%.¹ Medigap plans F and G will pay this limiting charge (excess charge). But other Medigap plans will not.²

If your doctor doesn’t accept assignment, you may have to pay the entire bill upfront and seek reimbursement for the portion that Medicare will pay. If you have to seek reimbursement from Medicare, you’ll use Form CMS 1490-S.

What's the difference between a participating provider and a non-participating provider?

Participating Medicare providers are those who have agreed to accept Medicare’s negotiated payments as payment in full for all Medicare services (this includes the patient’s deductible and coinsurance, as well as the portion that Medicare pays). In other words, they accept assignment for all services.¹

Non-participating providers don’t have to accept assignment for all Medicare services, but they may accept assignment for some individual services. If they accept assignment for a particular service, they can’t bill the patient for any additional amounts beyond the regular Medicare deductible and coinsurance, for that specific treatment.

What does it mean if a provider has opted out of Medicare?

Providers can go a step beyond non-participation, by opting out of Medicare altogether – although a very small fraction of providers take this option. Only about 1% of all non-pediatric physicians have opted out of Medicare.³

In that case, they have no contract at all with Medicare, leaving patients with potential exposure to higher out-of-pocket costs. If a Medicare enrollee sees a doctor who has opted out of Medicare, the patient is responsible for the full bill – the provider cannot bill Medicare, and Medicare will not reimburse the patient for any of the charges.¹ Providers who have opted out of Medicare have to disclose this information to patients with Medicare.

Medicare publishes monthly reports showing which providers have opted out. The out-out period lasts for two years. After that, a provider can opt back in or can continue to opt-out; CMS currently uses an automatic renewal provision, so providers who have opted out can continue that approach without contacting CMS every two years.⁴

Nationwide, more than 12,000 physicians had “opted out” of Medicare as of 2024. These providers can’t treat Medicare beneficiaries unless they enter into a private contract, with the patient agreeing to pay full price. Although only about 1% of non-pediatric physicians have opted out of Medicare, the specifics vary by specialty; 39% of those who have opted out are psychiatrists.³