How Does a Medigap Work With Original Medicare?Medigaps pay after Original Medicare for some or all of the costs that Original Medicare does not pay. If you have Original Medicare and a Medigap, and you receive a Medicare-covered service, Medicare pays first and the Medigap pays second.

Let’s say you have Original Medicare and a Medigap and you go to a nearby outpatient clinic to get a medically necessary chest x-ray. First, Original Medicare pays 80% of the Medicare-approved amount for your chest x-ray. Then the Medigap covers part or all of the remaining 20% percent coinsurance. If you did not have a Medigap, you would have to pay the coinsurance out of pocket.

A Medigap is not like other types of secondary insurance you may be used to. When you have secondary insurance, such as retiree coverage, the retiree plan makes decisions about whether or not it will pay for a service after Medicare pays. Even though Medigaps are offered through private insurance companies, they do not make their own coverage decisions. Using the x-ray example from before, this means that because Medicare covered the chest x-ray, the Medigap cannot deny payment for part of all of the remaining 20% coinsurance.

Read Next: What is Medicare SELECT?
Find Out: How Do Medigaps Work in Massachusetts, Minnesota, and Wisconsin?
Return to: Medicare Supplement

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