Questions & answers · Health insurance
When does my Medicare coverage start, and what if I sign up late?
Health insuranceBuying a policyChecked Nov 5, 2026
From K.Actuary, founded by Sangmin Kwon, ASA · sources checked 2026-11-05 · Source: Medicare.gov · When does Medicare coverage start? · page text View original ↗
In short
- Your first sign-up period lasts 7 months around your 65th birthday.
- Coverage always starts on the first of a month.
- If you miss it, you may pay a penalty for as long as you have Part B.
What this means
Medicare.gov says your first sign-up period lasts 7 months. It starts 3 months before you turn 65 and ends 3 months after your birthday month [1]. Coverage starts on the first day of a month [1].
With premium-free Part A, coverage starts the month you turn 65. If your birthday is on the first of the month, it starts the month before [1]. For Part B, signing up before your birthday month means it starts in your birthday month. Signing up in that month, or in the 3 months after, means it starts the next month [1].
If you miss the 7 months, you can only sign up from January 1 to March 31. That is the General Enrollment Period. Coverage starts the month after you sign up [1]. You may pay a late penalty for as long as you have Part B [1].
Your next step
Find your 65th birthday month and count the 7 months. If you work and have job coverage, ask Social Security or Medicare before you delay.
Check it yourself
Special rules apply if you have job coverage or a disability — "Don't know yet" from the page quoted here.
Where this comes from (1)
[1] Medicare.gov · When does Medicare coverage start? · page text · checked 2026-11-05
It lasts for 7 months, starting 3 months before you turn 65 … Coverage always starts on the first of the month … If you qualify for premium-free Part A: Your Part A coverage starts the month you turn 65. (If your birthday is on the first of the month, coverage starts the month before you turn 65.) … Before the month you turn 65 The month you turn 65 The month you turn 65, or during the 3 months after The next month ……
How we found this
We matched your question to 1 official source, quoted the exact lines, and re-checked each quote against its source on 2026-11-05.
What we don’t know yet
Your own plan or notice may say something different. If your letter cites another rule, send it and we will look again.
Every answer is checked against the official rule it quotes.
Information only — not legal advice. Your plan, insurer or agency decides.
This answer quotes the official sources listed above, with the date we checked them. Your own policy, notice and state rules control. We are not your lawyer or your insurer. We don’t file, argue or negotiate claims for you — you send any letter or form yourself.
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Answer id CQ4720. Spotted an error? Tell us.