Medicare in Puerto Rico: How to Sign Up for Part B on Time

In Puerto Rico, Part B does not start on its own, even if you already get Social Security. You must sign up during your 7-month Initial Enrollment Period around your 65th birthday. Signing up on time keeps you clear of the Part B late penalty.

Key takeaways

• Part A usually starts on its own in Puerto Rico if you already get Social Security or Railroad Retirement benefits.
• Part B does not. You must ask Social Security for it.
• Your first sign-up window is 7 months: 3 months before your birthday month, that month, and 3 months after.
• The Part B penalty adds 10% for each full 12 months you could have had Part B but did not. You pay it as long as you have Part B.
• If you or your spouse have health coverage from current work, you can usually wait without a penalty.

Why doesn't Part B start automatically here?

Medicare treats Puerto Rico differently from the 50 states for Part B. In the states, people who already get Social Security are signed up for Part A and Part B. In Puerto Rico, they are signed up for Part A only.

Part B is medical insurance. It helps pay for doctor visits, outpatient care, tests and medical equipment. Getting it takes a separate step: you have to tell Social Security you want it. If you do nothing, you will not have Part B.

This surprises many people. A red, white and blue Medicare card arrives, and they think they are fully covered. Look at the card. If it lists only Hospital (Part A), you do not have Part B yet.

Does Part A start on its own in Puerto Rico?

Yes, for most people who already get benefits. If you get Social Security or Railroad Retirement Board benefits at least 4 months before you turn 65, Part A starts the first day of your birthday month. Your card comes in the mail about 3 months before your 65th birthday.

If you are not getting benefits yet, nothing starts on its own. You must sign up for both Part A and Part B through Social Security.

The takeaway: Part A usually needs no action, but Part B always does. These 2026 amounts are set each year and can change. Most people pay no Part A premium because they worked 40 or more quarters, as explained in Medicare Part A Premium: Work Credits and Who Pays Nothing.

When can you sign up for Part B?

Your first chance is your Initial Enrollment Period. It lasts 7 months. It starts 3 months before the month you turn 65, includes your birthday month, and ends 3 months after.

For example, if you turn 65 in June, your window runs from March 1 through September 30.

Sign up in the first 3 months if you can. Then Part B can start the first day of your birthday month. If you sign up in your birthday month or later, Part B starts the first day of the next month.

If you miss this window and have no job-based coverage, your next chance is the General Enrollment Period, January 1 to March 31. Part B then starts the first day of the month after you sign up. A late penalty may apply.

How does the Part B late penalty work?

The penalty adds 10% to your Part B premium for each full 12-month period you could have had Part B but did not. You pay it for as long as you have Part B.

Here is one case. Say you wait 2 full years with no job-based coverage. Your penalty is 20%. In 2026, 20% of the $202.90 standard premium is about $40.58. You would pay about $243.48 a month instead of $202.90.

The standard premium is set every year, so the penalty amount changes with it. You can read more in The Part B Late Enrollment Penalty: How It Works and How to Avoid It.

Can you delay Part B while still working?

Yes, if you or your spouse are still working and have group health coverage through that job. You can wait to get Part B, without a penalty, while that coverage lasts.

When the job or the coverage ends, whichever comes first, you get a Special Enrollment Period (a sign-up window outside the usual dates). It lasts 8 months. If you sign up during that time, no Part B penalty applies.

Some coverage does not count. COBRA (coverage you keep for a while after leaving a job) and retiree coverage are not coverage from current work. Do not wait for them to end before you sign up. For more, see Working Past 65? When to Delay Medicare Enrollment.

How do you sign up for Part B?

You sign up through Social Security, not through a private insurance company. You can do it in three ways:

• Online at ssa.gov/medicare.
• By phone at Social Security, 1-800-772-1213 (TTY 1-800-325-0778).
• In person at a local Social Security office in Puerto Rico.

The form is CMS-40B, the Application for Enrollment in Part B. If you sign up after job coverage ends, you also send CMS-L564. Your employer fills it out to show the dates you had work coverage.

Keep a copy of everything you send. Write down the date and the name of anyone you speak with. That record helps if a question about your dates comes up later.

What should you check after signing up?

Watch for a letter from Social Security with your Part B start date. A new Medicare card will list Medical (Part B) and its start date.

Your Part B premium is usually taken out of your Social Security payment. If you do not get benefits yet, Medicare sends you a bill.

With Part A and Part B, you can stay in Original Medicare or join a Medicare Advantage plan. You need both parts to join a Medicare Advantage plan. Plans, costs and networks vary by carrier and location, and Medicare's Plan Finder at Medicare.gov lists the plans in your area.

If you want a Medigap policy (insurance that helps pay costs Original Medicare does not), timing matters. Your one-time 6-month Medigap Open Enrollment Period starts the month you are 65 or older and enrolled in Part B. Delaying Part B also delays that window.

Have questions? Call 1-877-443-3251 to talk it through with a licensed insurance agent. You never pay the agent; the plans they represent do, and the decision stays yours.

We do not offer every plan available in your area. Please contact Medicare.gov or 1-800-MEDICARE to get information on all of your options. Medicare has neither reviewed nor endorsed this information.