What is my Part D penalty?
Enter how many full months you went without Medicare drug coverage. The calculator shows the late enrollment penalty added to your premium each month.
- Penalty a month
- $5.50
With 14 months without drug coverage, your Part D penalty is $5.50 a month in 2026.
- Penalty percent
- 14%
- National base premium
- $38.99
- Penalty a year
- $66.00
Penalty a month: $5.50. With 14 months without drug coverage, your Part D penalty is $5.50 a month in 2026.
The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use
How to calculate
Works out the Medicare Part D late enrollment penalty: 1% of the national base premium for each month you went without drug coverage, for 2026 or 2027.
Example with the default inputs (Months without drug coverage 14, Year 2026): With 14 months without drug coverage, your Part D penalty is $5.50 a month in 2026.
Method: Penalty a month = months without coverage × 1% × national base beneficiary premium ($38.99 in 2026, $41.33 in 2027), rounded to the nearest $0.10.
- Only full months count, from the end of your initial enrollment period (or the end of your last creditable coverage) to when your Part D coverage starts.
- A gap of fewer than 63 days in a row adds no penalty.
- People who get Extra Help pay no late enrollment penalty.
- Medicare decides the count of months; this page uses the number you enter.
Worked examples
Each example is checked against the calculator on every build.
- Months without drug coverage 14, Year 2026 gives Penalty percent 14%, National base premium $38.99, Penalty a month $5.50, Penalty a year $66.00.Source: Medicare.gov, Avoid late enrollment penalties (https://www.medicare.gov/basics/costs/medicare-costs/avoid-penalties): $38.99 × 0.14 = $5.46, rounded to the nearest $0.10 = $5.50
- Months without drug coverage 25, Year 2026, Your plan’s monthly premium $45.50 gives Penalty a month $9.70, Penalty a year $116.40, Total premium a month $55.20.Source: Medicare.gov rule (1% a month of $38.99, nearest $0.10): 38.99 × 0.25 = 9.7475, $9.70
- Months without drug coverage 14, Year 2027 gives National base premium $41.33, Penalty a month $5.80, Penalty a year $69.60.Source: CMS fact sheet, July 28, 2026 (https://www.cms.gov/newsroom/fact-sheets/medicare-part-d-2027-national-average-monthly-bid-amount-information): 2027 base premium $41.33
- Months without drug coverage 500, Year 2026 gives Penalty a month $195.00.
- Months without drug coverage 0, Year 2026, Your plan’s monthly premium $12.00 gives Penalty a month $0.00, Total premium a month $12.00.Source: Medicare.gov: no months without creditable coverage means no penalty
How it works
National base beneficiary premium (CMS):
| Year | Base premium a month |
|---|---|
| 2026 | $38.99 |
| 2027 | $41.33 |
Penalty percent = 1% for each full month without creditable drug coverage.
Penalty a month = months × base premium ÷ 100, rounded to the nearest $0.10. A value exactly half way between two dimes rounds up.
Penalty a year = penalty a month × 12.
Total premium a month = your plan's premium + penalty a month, when you enter a plan premium.
Assumptions
- Only full months count: from the end of your initial enrollment period, or the end of your last creditable coverage, to the month your Part D coverage starts.
- Gaps of fewer than 63 days in a row add nothing.
- Extra Help removes the penalty; this page does not check for it.
- Medicare decides the number of months. The page uses the number you enter.
When the data is out of date
The page has base premiums for 2026 and 2027. After December 31, 2027 it keeps the 2027 premium until it is updated, and says so above the result.
Worked examples by hand
14 months, 2026. 38.99 × 14 ÷ 100 = 5.4586, which rounds to $5.50 a month, or $66.00 a year. This is the example on Medicare.gov.
25 months, 2026, with a $45.50 plan. 38.99 × 25 ÷ 100 = 9.7475, which rounds to $9.70. Total = 45.50 + 9.70 = $55.20 a month.
14 months, 2027. 41.33 × 14 ÷ 100 = 5.7862, which rounds to $5.80.
500 months, 2026. 38.99 × 500 ÷ 100 = 194.95, exactly half way, which rounds up to $195.00.
Other questions people ask
How is the Part D late enrollment penalty calculated?
Medicare multiplies 1% of the national base beneficiary premium by the number of full months you went without Part D or other creditable drug coverage, and rounds to the nearest $0.10. Fourteen months in 2026 is 38.99 × 0.14 = $5.46, so $5.50 a month.
What is the national base beneficiary premium for 2026?
It is $38.99 a month for 2026. CMS set it at $41.33 for 2027.
How long do I pay the Part D penalty?
Usually for as long as you have Medicare drug coverage, even if you change plans. The penalty is worked out again each year from that year’s base premium, so the dollar amount can change.
How long can I go without drug coverage before a penalty?
A gap of 63 days or more in a row without Part D or other creditable coverage, after your initial enrollment period ends, starts the penalty. Shorter gaps do not count.
Can I avoid or remove the penalty?
People who qualify for Extra Help do not pay it. If you think Medicare counted months when you had creditable coverage, you can ask for a reconsideration.