Income limits and how to apply, written for where you live.
All 50 statesMiss your Medicare window and you pay for it forever
The Part B late enrollment penalty is not a one-time charge. It is 10% more on your premium for every full year you waited, every month, for as long as you have Part B. Enter your date of birth and this tool returns your exact window, whether you can safely delay, and the exact dollar being late would cost.
Your Enrollment Plan
Medicare · 2026 rules
What is your date of birth?
Your enrollment window is built around the month you turn 65, and if you were born on the first of a month the dates shift. We need the exact day.
None of this is saved unless you ask us to email you the plan.
What the screen gives back
Your exact dates
The day your window opens and the day it closes, worked out with the first-of-the-month rule almost no article applies.
Whether you can delay
A straight verdict, not an "it depends." Employer size, COBRA, retiree coverage, and VA each give a different answer.
What being late costs
The exact dollar added to your premium every month, for life. One year late is $20.30 a month.
Three ways people miss it without knowing
An employer with fewer than 20 employees
It is not the penalty: months on a plan from current work never count against you, at any size. It is who pays first. Below 20, Medicare pays first — and if you do not have Part B, Medicare pays nothing and the work plan may refuse that share. People find this out with a bill.
COBRA and retiree coverage
Both come from a job you have already left, and Medicare's rule is about current employment. Neither gives you the 8-month Special Enrollment Period and neither pauses the penalty.
A birthday on the first of the month
Social Security treats you as attaining an age the day before your birthday. If you were born on a first, your entire window shifts back a month, and the final month you thought you had is already gone.
What if you did not have to pay the $202.90?
Medicare Savings Programs pay the Part B premium outright for people under their income limits, and they enroll year-round rather than waiting for a window. About half the people over 65 who run our screener qualify for one.
Check the savings programs →Common questions
When exactly can I sign up for Medicare?
Your Initial Enrollment Period is seven months long: the three months before the month you turn 65, the month itself, and the three months after. There is one exception almost nobody is told about. If you were born on the FIRST day of a month, Social Security treats you as turning 65 in the previous month, so your entire window shifts a month earlier. Someone born June 1 has a window that opens February 1 and closes August 31, not March 1 to September 30.
What is the Medicare Part B late enrollment penalty?
It is 10% of the standard Part B premium for each full 12-month period you could have had Part B and did not, and you pay it for as long as you have Part B. At the 2026 standard premium of $202.90 a month, one full year late means $20.30 extra every month, about $244 a year, for the rest of your life. The penalty is figured against each year's standard premium, so it rises when the premium rises. Only full 12-month periods count, which means eleven months late costs nothing extra and thirteen months late costs ten percent forever.
Can I delay Part B if I am still working?
Yes, and the size of the employer does not change that. Months you were covered by a group health plan because of current employment are excluded from the late enrollment penalty count, and the statute that does the excluding does not mention employer size. What 20 employees decides is something different: who pays your bills first. At 20 or more, the group plan pays first and Medicare pays second. Below that it flips, and if you do not have Part B then Medicare pays nothing and your work plan may refuse the share Medicare was supposed to cover. So at a small employer the risk is not a penalty, it is an unpaid bill. One caveat that applies at any size: the exclusion has to be provable, and the proof is form CMS-L564 signed by the employer.
Does COBRA count as coverage that lets me delay Part B?
No, and this is the most expensive misunderstanding in Medicare. The rule is about coverage from a job someone is working RIGHT NOW. COBRA continues a former employer's plan, so it does not give you a Special Enrollment Period and it does not pause the penalty clock. Retiree coverage from a former employer works the same way. So do Marketplace plans and VA health care on its own. Only current employment counts.
What happens if I already missed my window?
You enroll during the General Enrollment Period, January 1 through March 31 each year. Coverage now begins the first day of the month after you enroll — that changed recently, and a lot of still-published advice says July 1, which is the old rule. You will owe the late penalty, but there is one thing worth knowing: if someone at Social Security or Medicare gave you wrong information and you relied on it, you can request equitable relief, which can remove the penalty and backdate the enrollment. It is rarely mentioned and it is a real request you can make.
Is there any way to avoid paying the Part B premium?
Yes, for people under the income limits. Medicare Savings Programs pay the Part B premium outright, and unlike enrollment windows they accept applications year-round. About half of the people over 65 who run our screener qualify for one. That is separate from this tool and worth checking regardless of where you land on the enrollment calendar.