Updated: March 19, 2026
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Sign up for Medicare through Social Security online, by phone or in person during your seven-month enrollment window.
Missing your initial enrollment period triggers permanent 10% penalties for each year you delay Part B coverage.
Automatic Medicare enrollment only happens if you're already receiving Social Security benefits four months before turning 65.
Most people are automatically enrolled, but if you're not, you can work through Social Security online, by phone or in person. Sign up during the first three months of your enrollment window to avoid coverage gaps, and your coverage starts the first day of the month after you enroll (or your birthday month if you enroll during that time).
Your enrollment window runs seven months: three months before you turn 65, your birthday month and three months after. Enroll in those first three months, and your coverage kicks in on the first day of your birthday month.
Once you're all set, your Medicare card shows up within two to four weeks after approval, and Social Security sends a welcome packet with helpful information about what comes next.
The whole thing takes maybe 10 to 30 minutes, depending on your situation. You'll set up a Social Security account through Login.gov or ID.me. You can apply for Medicare even if you're not ready to start Social Security retirement benefits yet.
What you'll need:
Reps are available Monday through Friday, 8:00 a.m. to 7:00 p.m. Just tell them you want Parts A and B together, or only Part A. Worked for a railroad? You'll call the Railroad Retirement Board instead at 1-877-772-5772.
Call the number above to book an appointment, or head to ssa.gov to find the office nearest you.
65 marks an important health care transition. Medicare enrollment follows specific windows with firm deadlines; missing them means paying penalty premiums that last your entire life.
Most people think Medicare coverage starts automatically at 65. The reality is more nuanced: you must actively enroll during designated periods, and each enrollment window determines when your benefits begin.
Initial Enrollment Period | 7 months total: 3 months before your 65th birthday, your birthday month, plus 3 months after | Anyone turning 65 for the first time | Depends on when you sign up during those 7 months | You'll wait until January to enroll and pay penalties |
General Enrollment Period | January 1 - March 31 every year | People who missed their first chance and don't qualify for special circumstances | The month after you sign up | 10% penalty for every year you waited |
Special Enrollment Period | Usually 8 months after qualifying events like losing job coverage | People with life changes like retirement or moving | Typically the month after enrollment | None if you truly qualify |
Annual Open Enrollment | October 15 - December 7 | Current Medicare members changing plans | January 1st | No penalties for switching plans |
So you missed your Medicare enrollment window but you're definitely not alone in this. Thousands of people find themselves in your exact situation every year, and there are still options available.
If you had employer coverage, TRICARE or other qualifying coverage when you turned 65, you'll get eight months from when that coverage ends or when you turn 65 (whichever is later) to sign up penalty-free.
But if you don't qualify for that special window, you'll need to wait for the General Enrollment Period that runs from January 1 through March 31. The downside? You'll face penalties during this route. Your coverage will start July 1 regardless of when during the General Enrollment Period you enroll.
Turning 65 doesn't automatically trigger Medicare enrollment for everyone. Whether Medicare shows up on its own depends on what's happening with your Social Security benefits.
If you're already collecting Social Security or Railroad Retirement Board benefits at least four months before your 65th birthday, you're all set. Medicare will enroll you in both Part A and Part B automatically, and your card will arrive in the mail about three months before coverage kicks in. You don't need to do anything.
But if you're not receiving Social Security benefits yet, you're still working or waiting to claim, then you'll need to sign up yourself. Contact the Social Security Administration about three months before turning 65. The online application at SSA.gov is the fastest way to get enrolled.
You'll get automatic enrollment if:
You're receiving Social Security retirement benefits at least four months before turning 65.
You've been getting Social Security disability benefits for 24 months (coverage starts on your 25th month).
You have ALS (Lou Gehrig's disease) and receive disability benefits, then there's no waiting period, and coverage begins immediately.
You're a Railroad Retirement Board beneficiary who meets the same four-month timing.
You turned 65, whether you were still working or just didn't realize you needed to actively sign up. The government doesn't make these deadlines easy to understand. Now you're wondering what this mistake will cost you, and there are real financial consequences.
But the worst thing you can do is keep waiting because you're overwhelmed or embarrassed. Every month you delay makes it more expensive.
You'll pay a 10% penalty for each full year you could've signed up for Part B but didn't. This isn't a "pay a fee and move on" situation. It gets added to your monthly premium forever. The standard Part B premium is $185 in 2025. If you delayed two full years before enrolling, you'd pay a 20% penalty plus the standard premium: that's $222 every month for as long as you have coverage.
And it gets worse the longer you wait. Three years means a 30% penalty. Four years means 40%. People who waited five years now pay over $270 monthly instead of $185. Most of the time, they just didn't understand the rules.
Miss drug coverage for more than 63 days and you'll pay 1% of what Medicare calls the base premium (about $37 in 2025) each month you went without coverage. So if you delayed drug coverage for 14 months, you'd pay a 14% penalty on top of your monthly plan premium for life.
Even if you never take medication, this penalty adds up. That 14% penalty could cost you hundreds of extra dollars over the years.
You can avoid penalties if you qualify for a Special Enrollment Period due to certain life events, but situations like losing COBRA coverage or retiree coverage don't qualify. The rules are pretty strict about what counts.
Signing up for Medicare requires action on your part unless Social Security benefits already flow to your account. You get seven months around your 65th birthday to complete enrollment, but delays cost you permanently. Every year you wait adds a 10% penalty to your Part B premiums for life.
We've compiled answers to the most common how to sign up for Medicare questions in our frequently asked questions below:
Contact Social Security three months before turning 65 unless you're already receiving Social Security benefits. You can apply online at ssa.gov, call 1-800-772-1213 or visit your local Social Security office during your seven-month enrollment window.
You can sign up through Social Security in three ways: online at ssa.gov (10-30 minutes), call 1-800-772-1213 (Monday-Friday, 8 a.m.-7 p.m.) or visit your local Social Security office. All methods require the same basic information and documents.
Your Medicare card arrives within two to four weeks after approval. Coverage starts based on when you enroll: the first day of your birthday month if you enroll early, or the month after enrollment during later periods.
You need your Social Security number, birth certificate (or proof of U.S. citizenship) and bank information for direct deposit. If you have current health coverage, include insurance details. Social Security may request additional documents during processing.
You qualify at age 65, or earlier, with certain disabilities or conditions like ALS. You also need to be a U.S. citizen or legal permanent resident. Those receiving Social Security benefits automatically get enrolled four months before turning 65.
Medicare isn't mandatory, but delaying Part B enrollment results in permanent 10% penalties for each year you wait. You can delay without penalties only if you have qualifying employer coverage and if you’re unemployed, then any other creditable insurance.
About Mark Fitzpatrick
Mark Fitzpatrick, a Licensed Property and Casualty Insurance Producer, is MoneyGeek's resident Personal Finance Expert. He has analyzed the insurance market for over five years, conducting original research for insurance shoppers. His insights have been featured in CNBC, NBC News and Mashable.
Fitzpatrick holds a master’s degree in economics and international relations from Johns Hopkins University and a bachelor’s degree from Boston College. He's also a five-time Jeopardy champion!
He writes about economics and insurance, breaking down complex topics so people know what they're buying.
