Medicare Supplement, or Medigap, plans help cover expenses that Original Medicare may not pay. But for some people, having two different health plans can be confusing and a bit daunting. Read on to understand how to use your Medigap plan alongside Medicare effectively — so you can feel empowered, instead of anxious, when getting the healthcare you need.
Medicare cards to show your doctor
With a Medigap plan, you now have two insurance payers. Original Medicare is the primary payer of your insurance claims, and your new Medigap plan is the secondary payer. When you visit your doctor, hospital, or lab for treatment, you need to show both your red, white, and blue Medicare card and your Medigap ID card to prove coverage.
Talking with your doctor
Most healthcare providers accept Original Medicare, but it’s important to ensure the services you are receiving are covered. Your Medigap plan will only pay for services that are also covered by Medicare, like doctor and hospital visits and durable medical equipment.
You should also make sure your provider is in-network, so you don’t have to pay hidden fees. To determine this, ask the office, “Do you accept Medicare assignment?”
- If they say yes, they’re a participating Medicare provider, and you’ll pay lower fees for your services (typically just the 20% coinsurance).
- If they say they accept Medicare, but not the “assignment”, they’re nonparticipating and can legally bill you 15% over the Medicare negotiated rate for the service.
When you visit your healthcare provider, be sure to tell them you have both plans. You can let them know by saying:
- “I have Original Medicare as my primary insurance and a Medicare Supplement (Medigap) plan [A, D, G, K, etc.] as my secondary payer.”
Medicare prior authorization pilot
Beginning in January 2026, six states are taking part in a Medicare pilot program meant to reduce the use of high-cost, high-risk procedures. When you need prior authorization for a medical service, it means that your doctor is required to get approval from Medicare before you have the treatment. If you don’t get approval, you can still receive the care, but you’ll have to pay for it out of pocket at the full price. Because this impacts Original Medicare, people with Medigap plans will be included in this new requirement.
Prior authorization for these services will only be required in states taking part in the pilot program. These states are:
- Arizona
- New Jersey
- Ohio
- Oklahoma
- Texas
- Washington
Prior authorization (or pre-authorization) will be required for some services, including:
- Deep brain stimulation for essential tremor and Parkinson’s disease
- Cervical fusion
- Incontinence control devices and nerve stimulation for urinary incontinence
- Diagnosis and treatment of impotence
- Epidural steroid injections for pain management
If you think a service you need is included in the list for pre-authorization, make sure your doctor submits a request before performing the treatment. This may mean you have to wait a little longer to receive the service. If your pre-authorization is denied, you have the right to appeal that decision through the Center for Medicare and Medicaid Services (CMS).
Medicare Supplement billing process
Even though you have two payers for your healthcare services, there shouldn’t be any extra paperwork that you have to take care of for your healthcare bills to be paid. Original Medicare and your Medigap plan pay bills through what’s known as crossover.
Medicare crossover explained
Medicare is the first payer on your medical bills. Once it has paid its share for your treatment, it sends a digital signal (the crossover) to your Medigap carrier. Once they receive the transmission, your Medicare Supplement plan then pays the extra coinsurance and deductibles that it covers
Medicare Supplement and unexpected bills
If you receive an unexpected Medicare Supplement bill from your healthcare provider, don’t worry. Sometimes your doctor will send it to you before the Medigap payment has finished processing. If you have questions, you can call your healthcare provider’s office or log into your Medigap carrier’s online portal to see if the claim has been processed.
Using your Medigap plan doesn’t have to be a complicated process. If you have questions about coverage or concerns over unexpected bills, log into your supplement provider’s website or reach out to the customer service number on the back of your Medigap card.