What happens if you don’t sign up for Medicare?

The penalties for not enrolling when you are first eligible for Medicare depend on the part of Medicare.

Part A

If you choose not to sign up for Medicare Part A when you become eligible, a penalty may be assessed. This penalty depends on why you chose not to sign up.

If you simply chose not to sign up when you were first eligible, your monthly premium — if you have to pay one — will increase by 10% for twice the number of years that you went without signing up. For example, if you waited two years to sign up, you will pay the late enrollment penalty for 4 years after signing up.

Part B

The penalty for Medicare Part B is a little different than Part A. If you choose not to sign up for Medicare Part B when you first become eligible, you could face a penalty that will last much longer than the penalty for Part A.

The Part B penalty is 10% of the standard premium for each 12-month period you were not signed up, and you will have to pay this penalty for as long as you are enrolled in Medicare.

For example, if you waited 1 year past your initial enrollment period to sign up for Part B, your premium price will increase by 10% for the rest of the time you are enrolled. If you waited 2 years to sign up past your initial enrollment period, your premium will increase by 20% for the rest of the time you are enrolled.

Part C

Medicare Part C (Medicare Advantage) is optional and does not have penalties on its own, but penalties may be included for late enrollment in the parts of Medicare included within your Medicare Advantage plan.

Part D

Medicare Part D is not a mandatory program, but there are still penalties for signing up late. If you don’t sign up for Medicare Part D during your initial enrollment period, you will pay a penalty amount of 1% of the national base beneficiary premium multiplied by the number of months that you went without Part D coverage.

In 2025, the national base benefic

iary premium is $36.78 and changes every year. If you have to pay the penalty, the penalty amount will be rounded to the nearest $.10, and this amount will be added to your monthly Part D premium for the rest of the time you are enrolled.

If you disagree with the penalty you are assessed, you can appeal the decision, but must continue to pay the penalty along with your premium. Your prescription drug plan can drop your coverage if you fail to pay the premium or penalty.