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Medicare penalties are unusual among insurance charges because they do not expire. Miss your enrollment window without qualifying coverage and the extra amount is added to your premium for as long as you hold the coverage, which for most people means the rest of their lives. The Part B penalty is the expensive one: 10% of the standard premium for every full 12 months you were eligible and did not enroll. At the 2026 standard premium of $202.90, a two-year delay adds $40.58 a month, or about $487 a year, forever.
This guide works through the dollar math for Part A, Part B, and Part D penalties at 2026 rates, and the coverage that protects you from each one.
Part B: 10% per year, for life
The Part B penalty counts full 12-month periods. An 18-month delay counts as one full period, so the penalty is 10%. A 24-month delay counts as two periods, so the penalty is 20%. Here is what common delays cost at the 2026 standard premium:
- 1 year late: 10% penalty, $20.29 extra a month, premium of $223.19
- 2 years late: 20% penalty, $40.58 extra a month, premium of $243.48
- 3 years late: 30% penalty, $60.87 extra a month, premium of $263.77
- 5 years late: 50% penalty, $101.45 extra a month, premium of $304.35
The penalty is a percentage of the current standard premium, so it grows as the standard premium grows. Someone who pays an extra $487 in 2026 will pay more than that in later years on the same penalty percentage. Over a 20-year retirement, a two-year delay costs well over $10,000 in extra premiums. Our guide to the Medicare enrollment window at 65 covers the dates that start this clock.
Part D: 1% per month without drug coverage
The Part D penalty builds by the month. For every month you go without Part D or other creditable drug coverage after your initial eligibility, Medicare adds 1% of the national base beneficiary premium to your eventual Part D premium. The base premium for 2026 is $38.99, so each uncovered month adds about $0.39, rounded to the nearest ten cents.
Fourteen uncovered months produce a penalty of 14%, which is $5.50 a month added to your plan premium for life. Three years uncovered produce 36%, about $14.00 a month. The penalty is recalculated each year from that year’s base premium, so the dollar amount drifts upward over time. It does not apply while you have creditable coverage, and it never starts if you enroll within 63 days of losing creditable coverage. People who receive Extra Help do not pay it.
Creditable means the coverage is expected to pay at least as much as standard Part D on average. Employer and union plans usually qualify, and your plan is required to tell you each year whether your coverage is creditable. Keep those notices. If Medicare later questions your coverage history, the notices are your proof.
Part A: a smaller, time-limited penalty
Most people get Part A premium-free and never face a Part A penalty. If you have to buy Part A and you enroll late, the penalty is 10% of the premium, and you pay it for twice the number of years you delayed. Delay two years on the reduced 2026 premium of $311 and you pay an extra $31.10 a month for four years. It is real money, and it is the only one of the three penalties that eventually ends. Our guide to Medicare Part A premium costs explains who has to buy Part A in the first place.
Coverage that protects you, and coverage that does not
The main protection is a special enrollment period tied to active employment. If you or your spouse are covered by a group plan from an employer with 20 or more employees, you can delay Part B without penalty and enroll within eight months after the employment or the coverage ends, whichever comes first.
The traps are the forms of coverage that feel equivalent and are not. COBRA does not protect you from the Part B penalty, and your eight-month clock runs from the end of employment, not the end of COBRA. Retiree coverage does not protect you either. Marketplace plans do not count as employer coverage for this purpose. Coverage from an employer with fewer than 20 employees usually leaves Medicare as the primary payer, which means delaying Part B can leave you both penalized and underinsured. Our explainer on working past 65 with employer coverage goes case by case.
If you already owe a penalty
There is no general amnesty. Social Security can remove a Part B penalty if you can show you had qualifying coverage, or in limited cases where you were given wrong information by a federal employee. That is worth pursuing if your facts fit, because the saving compounds for decades. Otherwise the penalty stays, and the practical move is to stop it from growing: enroll at the next opportunity rather than letting another 12-month period roll by. Each additional full year of delay adds another 10% to Part B, permanently.
