Medicare late enrollment penalties

A penalty is a higher premium, not a fee

Medicare's late enrollment penalties are not charged once. They are added to your monthly premium, they grow with the length of time you went without coverage, and for Part B and Part D they usually last as long as you keep that coverage. For most people that means the rest of their life. The Part A penalty works differently.

Part B: 10% for each full year

If you could have signed up for Part B but did not, and you had no coverage from a current job that let you wait, your premium goes up 10% for every full 12 months you went without it. Medicare's own 2026 example: someone who waited 24 months owes a 20% penalty, so the standard $202.90 premium becomes $243.50 a month. Because the penalty is a percentage of the standard premium, it changes when the premium does.

Part D: 1% for each month

The drug penalty applies if, after you first become eligible, you go 63 days or more in a row with neither Part D nor other creditable drug coverage. Medicare figures it from an amount it calls the “national base beneficiary premium”: 1% of that amount for each month you were without coverage, or 12% for a full year. In 2026 that base premium is $38.99, so a 14-month gap adds a penalty of $5.50 a month on top of your plan's premium. The base premium is reset every year, so the dollar amount moves with it, and the penalty follows you even if you switch plans.

Creditable coverage is drug coverage that is similar in value to Part D, for example from some employer or union plans. Before you rely on it, ask the plan in writing whether its drug coverage is creditable, and keep the answer.

Part A: only if you have to buy it

Most people get Part A without a premium and never face this one. If you must buy Part A and pass on it when you first qualify, your premium can rise 10%, and the higher rate lasts twice as long as the delay. Two years late means four years at the higher rate.

When you will not owe a penalty

The safest course is to sign up during your Initial Enrollment Period at 65, or to confirm in writing that your current coverage lets you wait. If money is tight, see Extra Help and Medicare Savings Programs.

Common questions

Last reviewed October 2026. Medicare rules, dates and dollar amounts can change each year; Medicare.gov has the official details.