If you sign up for Medicare before you get Social Security, Medicare bills you for your Part B premium, and the first bill can be larger than expected. Medicare.gov says your first bill may include premiums for earlier months not yet billed plus the next 3 months, so it can cover up to 6 months. After that, bills come every 3 months, until Social Security payments begin and premiums can come out automatically.
Why is my first bill so high?
Medicare.gov gives an example. Say your coverage starts February 1:
- Your first bill is dated March 28.
- It arrives around April 10.
- It's due April 25.
- It covers February, March, and April (the months already passed) and May, June, and July (the next 3).
So the first bill can be for 6 months of premiums. From then on, Medicare.gov says, bills are for 3 months at a time.
CMS lists the standard Part B premium at $202.90 a month for 2026. Six months at the standard amount would be $1,217.40. Your amount may be higher if you pay an income-related adjustment or a late enrollment penalty.
For how premium deductions and notices work once you're set up, see Part B premium deductions from Social Security. This page focuses on the first bill and the switch to Social Security.
How do I pay the first bill on time?
The Medicare Premium Bill (form CMS-500) page says Medicare must get your payment by the 25th of the month. A few ways to make that date:
Pay online in your secure Medicare account. Medicare.gov calls this the fastest way to pay. It also says payments from a checking or savings account take about 5 business days to process, and card payments are faster. So paying at least 5 business days before the 25th gives you room. Medicare.gov says mailed payments take longer, so send a check early.
A simple plan for the first bill:
- Watch for the bill around the 10th of the month.
- Pay online the day it arrives, or at least 5 business days before the 25th.
- Keep the confirmation number.
Should I set up Medicare Easy Pay?
Medicare Easy Pay takes your premium from your bank account automatically. You can sign up in your Medicare account under "My Premiums," or by mailing form SF-5510.
Things to know:
- Medicare.gov says it can take 6 to 8 weeks for automatic deductions to start. Keep paying your bills until you see that Easy Pay has begun.
- The amount updates automatically when your premium changes.
- If Medicare can't set it up, it sends a letter explaining why.
What happens when my Social Security payments start?
Medicare.gov says that once your Social Security benefit is enough to cover your premium, your Medicare premiums will be automatically deducted from it.
When that happens, Medicare.gov says you should:
- Stop Medicare Easy Pay, if you use it. It can take up to 4 weeks for deductions to stop.
- Contact your bank to stop any online bill payments you set up.
That way, you don't pay twice.
You may also get a notice from Social Security about retroactive payments. Medicare.gov says if you get one, you might need to adjust how you pay your premiums.
What if I paid twice?
It can happen during the switch. Check:
- Your bank statements for Medicare payments.
- Your Social Security benefit statement for premium deductions.
- Your Medicare account, under "My Premiums," for payments received.
What to say when you call 1-800-MEDICARE (1-800-633-4227):
"I think my Part B premium for [months] was paid twice: once by [Easy Pay / bank payment] and once from my Social Security benefit. Can you check my premium account and tell me how a credit or refund would be handled?"