How to Avoid Medicare Late Enrollment Penalties for Part B and Part D

What are Medicare late enrollment penalties?

Medicare late enrollment penalties are extra charges added to your monthly premium if you don’t sign up for Part B or Part D when you’re first eligible and don’t have other qualifying coverage. They generally last as long as you have that coverage, which for most people means for life.

The penalties exist to encourage people to enroll while they’re healthy, not only after they need care. That makes sense for the program as a whole, but it can be an unpleasant surprise if you delayed signing up because you believed you didn’t need the coverage yet or that another plan had you covered.

The good news is that both penalties are avoidable with good timing and a little paperwork. Often, a penalty traces back to a misunderstanding about employer coverage, retiree plans or COBRA rather than to someone ignoring Medicare. Knowing the rules ahead of time is the simplest protection you have, and it costs nothing but a little planning.

How is the Part B late enrollment penalty calculated?

The Part B penalty is 10% of the standard Part B premium for each full 12-month period you could have had Part B but didn’t, without qualifying coverage. It’s added to your premium for as long as you have Part B, and because it’s a percentage, it grows when the standard premium grows.

Here’s an example using 2026 figures. Say you delayed Part B for 2 full years without qualifying coverage. Your penalty would be 20% of the standard premium. With the 2026 standard premium of $202.90, that’s about $40.58 more each month, for a total of about $243.48. CMS hasn’t announced the 2027 premium yet.

Partial years don’t count toward the penalty. A delay of 23 months counts as only one full 12-month period, so the penalty would be 10%. You can run your own numbers with our Part B penalty calculator; the result is an estimate to help you plan, not a quote or an official figure.

The Part B penalty applies to the standard premium, and if your income means you pay more through IRMAA, your total Part B bill may be higher still. Kris is a licensed insurance agent, not a tax adviser, so check with your tax professional about income questions. Our Medicare FAQ covers related questions in plain English, too.

How is the Part D late enrollment penalty calculated?

The Part D penalty is 1% of the national base beneficiary premium multiplied by the number of full months you went without Part D or other creditable drug coverage, rounded to the nearest $0.10. It applies if you go 63 or more days in a row without creditable drug coverage.

Here’s a worked example for 2027, when the base premium is $41.33. If you went 20 full months without creditable coverage, the math is 20 × 1% × $41.33 = $8.27, which rounds to $8.30 a month. That amount is added on top of whatever premium your drug plan charges.

Because the base premium changes each year, Medicare recalculates the dollar amount annually, and the penalty generally lasts as long as you have Part D. Try your own numbers with our Part D penalty calculator, which gives an estimate only, so you can see how a gap might add up.

What counts as creditable drug coverage?

Creditable drug coverage is prescription coverage that’s expected to pay, on average, at least as much as standard Medicare Part D. If you have it, you can delay Part D without a penalty. Many employer, union and retiree plans qualify, but not all of them do, so it’s important to confirm.

Plans that offer drug coverage to Medicare-eligible people are required to tell you each year whether that coverage is creditable. Look for a “creditable coverage” notice from your employer or plan, often sent in the fall. Keep those notices with your important papers, because you may need them to prove you had coverage.

If your coverage isn’t creditable, or you simply aren’t sure, ask your benefits office in writing and keep their answer. Discount cards and drug coupons aren’t insurance and don’t count as creditable coverage, no matter how much they save you at the pharmacy. When in doubt, enrolling in a Part D plan on time protects you.

Also watch for changes. An employer can switch insurers or redesign its drug benefit, and coverage that was creditable last year may not be this year. Read each new notice when it arrives, and if your coverage stops being creditable, you’ll generally have a window to join a Part D plan before a penalty begins to build.

Can you delay Part B if you’re still working?

Usually, yes. If you’re covered by a group health plan from your own or your spouse’s current job at an employer with 20 or more employees, that plan is generally primary and you can delay Part B without a penalty. When the job or coverage ends, you get an 8-month Special Enrollment Period.

That 8-month window starts when the employment or the group coverage ends, whichever happens first. To use it, you’ll typically file Social Security’s Part B application along with an employer form confirming your coverage dates. Start early, so paperwork delays don’t push you past the deadline and into a penalty.

Watch for a few common traps. COBRA and retiree coverage generally don’t count as coverage from current employment, and employers with fewer than 20 employees follow different rules. Our guide to turning 65 in Ohio covers the enrollment steps in order, and Social Security can confirm how the rules apply to your situation.

• Confirm your employer has 20 or more employees.
• Get a creditable coverage notice for your drug plan.
• Don’t rely on COBRA or retiree coverage to delay Part B.
• Sign up for Part B within 8 months of the job or coverage ending, whichever comes first.

Do late penalties still apply if you join Medicare Advantage?

Yes. To join a Medicare Advantage plan, you must have both Part A and Part B, so any Part B penalty stays with you. If your Medicare Advantage plan includes drug coverage, a Part D late penalty is added to that plan’s premium, just as it would be with a stand-alone drug plan.

Some people assume a low-premium Medicare Advantage plan makes a penalty disappear. It doesn’t. The penalty is tied to your Medicare record, not to the type of plan you choose, so it follows you from plan to plan and from year to year for as long as you have the coverage.

The same is generally true if you move. Whether you stay in Perrysburg, relocate across Ohio or spend winters in another state, the penalty generally travels with you. That’s why getting the timing right at the start matters far more than picking the perfect plan, since you can usually change plans later but can’t easily undo a penalty once it’s been applied.

What can you do if you missed your enrollment window?

If you missed your window and don’t qualify for a Special Enrollment Period, you can sign up for Part B during the General Enrollment Period, January 1 – March 31 each year, with coverage starting the month after you sign up. A late enrollment penalty may apply, so act as soon as you can.

For Part D, you can generally join a plan during Annual Enrollment, October 15 – December 7, 2026, for coverage starting January 1, 2027. The sooner you enroll, the fewer uncovered months are added to your penalty, so it rarely pays to wait another year once you know you need drug coverage.

If you believe a penalty was applied in error, for example because you actually had creditable coverage, you can ask for a review. Gather your coverage notices and employer forms, then contact Medicare or your plan. Kris can help you understand the letter you received and what your next steps might be.

How can Kris help you avoid penalties?

Kris Kryder can review your employer or retiree coverage, help you time Part B and Part D correctly and compare plans from the carriers she represents. The consultation is no-cost and no-obligation, and you can meet in person at the Perrysburg office or by phone or video, whichever is easier.

Call (419) 277-8097, Monday through Friday, 9:00 AM to 5:00 PM, or request a quote online. For official information, visit Medicare.gov or SSA.gov, and browse our Medicare FAQ for plain-English answers to common questions. If you’ve already received a penalty notice, bring it with you so Kris can review it alongside your coverage history.

The ideal time to call is a few months before you turn 65 or before you leave a job with group coverage. That gives you time to request employer forms, confirm creditable coverage and line up a start date. Kris is a licensed insurance agent, not a tax or legal adviser, so she may suggest you also check with those professionals.