You can add Medicare Part B during specific enrollment periods, or right when you turn 65
Medicare Part B covers doctor visits, outpatient care, and medical equipment. If you did not sign up for it when you first became may be able to access at 65, you can add it later — but the timing matters, because waiting can mean paying a higher premium for the rest of your life.
The easiest time to add Part B is during your Initial Enrollment Period, which runs for seven months: three months before the month you turn 65, the month you turn 65, and three months after. If you missed that window, you can still add it, but you will need to wait for the General Enrollment Period (January 1 through March 31 each year) and your premium will be 10 percent higher for each full year you delayed.
Key Takeaways
- Your Initial Enrollment Period is seven months long: three months before you turn 65, the month you turn 65, and three months after — this is when you can add Part B without a penalty.
- If you have employer coverage or are still working, you may not need to sign up right at 65; tell Social Security or Medicare about your work situation to avoid penalties.
- You can add Part B through Social Security, Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
- Part B has a monthly premium (the amount varies by income) plus a yearly deductible and copayments for services.
- If you miss your enrollment period and do not have a may have access to reason, you will pay a permanent 10 percent premium increase for each year you delayed.
When you can add Part B without a penalty
Your Initial Enrollment Period is your penalty-free window. It spans seven months total: the three months before the month you turn 65, the month you turn 65 itself, and the three months after. For example, if you turn 65 in June, your period runs from March through September.
There is one major exception: if you are still working and covered by your employer's health plan, you do not have to sign up for Part B at 65. You can delay without penalty as long as you are actively employed and covered by that employer plan. Once you leave that job or lose the coverage, you have eight months to add Part B without a penalty — this is called your Special Enrollment Period. You will need to show proof of your employer coverage (a pay stub, benefits letter, or insurance card) when you sign up.
If you are on COBRA (the temporary coverage you can buy after leaving a job), COBRA does not count as employer coverage for this purpose. You should add Part B before COBRA ends.
How to add Part B after you have missed the enrollment period
If your Initial Enrollment Period has passed and you do not have a may have access to reason to delay, you can still add Part B — but it will cost more. You can sign up during the General Enrollment Period, which runs January 1 through March 31 each year. Coverage starts July 1 of that year.
Your monthly premium will be 10 percent higher for each full 12-month period you went without Part B after you first became may be able to access. That increase is permanent — it does not go away. For example, if you were may be able to access at 65 but did not sign up until age 68, you would have delayed for three years, so your premium would be 30 percent higher than the standard amount for the rest of your life.
The only way to avoid this penalty is to have a may have access to reason for the delay. may have access to reasons include being covered by an employer plan, being covered by TRICARE (military health coverage), or living outside the United States. If you believe you have a may have access to reason, bring documentation when you sign up.
The steps to add Part B
You have four main ways to add Part B:
- Online at Medicare.gov: Go to Medicare.gov, sign in with your username and password, and look for the option to make changes to your coverage. You can add Part B from there. This is the fastest method if you are comfortable online.
- By phone: Call 1-800-MEDICARE (1-800-633-4227). Representatives are available Monday through Friday, 8 a.m. to 8 p.m. Eastern time. Have your Social Security number and Medicare card ready.
- At your local Social Security office: Find your office at ssa.gov/locator. You will need to bring your Social Security card, proof of citizenship or legal residency, and proof of age (birth certificate or passport).
- Through Social Security by phone: Call 1-800-772-1213 (TTY 1-800-325-0778) to speak with a Social Security representative about adding Part B.
Whichever method you choose, have your information ready: your full name, date of birth, Social Security number, and the date you want coverage to start (usually the first of the month).
What Part B costs and what it covers
Part B has three costs: a monthly premium, a yearly deductible, and copayments or coinsurance for each service. The monthly premium amount changes each year and is based on your income from two years prior. In 2024, the standard premium is $164.90 per month for most people, but higher earners pay more.
The yearly deductible (the amount you pay out of pocket before Part B starts paying) is $240 in 2024. After you meet the deductible, you typically pay 20 percent of the cost for doctor visits, lab tests, and imaging. Some preventive services (like annual wellness visits and cancer screenings) are covered at no cost.
Part B does not cover dental, vision, hearing aids, or long-term care. If you want coverage for those services, you can buy a separate Medigap policy or choose a Medicare Advantage plan (Part C), which bundles Part A, Part B, and usually Part D into one plan with different costs and coverage rules.
What happens after you add Part B
Once you sign up, Medicare will send you a new Medicare card in the mail within two weeks that shows your Part B coverage. Your coverage will start on the first of the month you requested, or the first of the following month if you sign up after the 15th.
You can use your Part B coverage right away at any doctor or hospital that accepts Medicare. Bring your new Medicare card to your appointments. If you have questions about what a service will cost before you go, you can call your doctor's office or ask Medicare directly.
If you also want prescription drug coverage (Part D), you can add that separately during the same enrollment period, or wait for the Annual Enrollment Period (October 15 through December 7 each year). Adding Part D late also carries a penalty if you go without it for more than 63 days after you first become may be able to access.
When to contact Medicare if something goes wrong
If your Part B coverage does not start on the date you expected, or if you are charged for a service you think Part B should cover, contact Medicare at 1-800-MEDICARE. Have your Medicare number and the date of service ready. Medicare can investigate billing problems and correct your account.
If you signed up late and believe you have a may have access to reason that should waive the penalty, you can request a review. You will need to submit written proof of your may have access to reason (such as an employer benefits letter or proof of residence outside the U.S.) to your local Social Security office or Medicare.
Frequently Asked Questions
What if I turned 65 more than a year ago and never signed up for Part B?
You can still add Part B during the General Enrollment Period (January 1 through March 31), and coverage will start July 1. Your premium will be 10 percent higher for each full year you delayed. If you believe you had a may have access to reason to delay (such as employer coverage), contact Social Security with proof to request a waiver of the penalty.
Do I have to add Part B if I have Medicare Part A?
Part A and Part B are separate. Part A covers hospital stays; Part B covers doctor visits and outpatient care. You do not have to take Part B, but if you delay past your enrollment period without a may have access to reason, you will pay a permanent premium increase. If you are unsure whether you need it, talk to your doctor or call 1-800-MEDICARE.
Can I add Part B in the middle of the year?
Outside of your enrollment periods, you can only add Part B during the General Enrollment Period (January 1 through March 31), and coverage will not start until July 1. If you have a may have access to life event (like losing employer coverage), you may have a Special Enrollment Period that allows you to add it outside these windows.
Will adding Part B affect my Social Security benefits?
Part B has a separate monthly premium that is deducted from your Social Security check if you receive benefits. Adding Part B does not change the amount of your Social Security payment itself, only the amount you receive after the Part B premium is taken out.
What if I want to drop Part B later?
You can drop Part B during the General Enrollment Period (January 1 through March 31), and the change takes effect July 1. However, if you drop it and want to add it back later, you will face the same late-enrollment penalty. Only drop Part B if you are certain you do not need it or if you are switching to a Medicare Advantage plan that includes Part B coverage.