Medicare is automatic after you've been on SSDI for 24 months, but you can refuse it

If you receive Social Security Disability Insurance (SSDI), Medicare enrollment happens automatically after you have been receiving benefits for 24 consecutive months. You do not have to do anything to trigger this enrollment—Social Security sends your information to Medicare, and your coverage begins on the first day of the 25th month. However, you are not legally required to accept Medicare. You can decline it, though doing so has real consequences for your healthcare costs and future enrollment.

The 24-month waiting period is a federal rule that applies to nearly all SSDI beneficiaries, regardless of age or health status. This is different from Medicare may be able to access based on age (65) or end-stage renal disease. The clock starts the month your SSDI benefits begin, not the month you filed or were approved.

Key Takeaways

  • Medicare Part A (hospital insurance) enrolls you automatically after 24 months on SSDI with no action required on your part.
  • You can refuse Medicare by contacting Social Security in writing before your coverage date, but you will lose the option to enroll penalty-free later.
  • If you have employer health insurance through work or a spouse's job, you may want to decline Medicare to avoid coordination-of-benefits issues, but this decision should be made carefully with your employer's benefits team.
  • Declining Medicare does not affect your SSDI payments, but it does mean you will pay the full cost of hospital and medical care out of pocket until you turn 65 or meet another Medicare rule.
  • If you decline and later change your mind, you can enroll during the General Enrollment Period (January 1–March 31 each year), but you will owe a late-enrollment penalty on Part B for each year you were not enrolled.

How the 24-month countdown works

The 24 months are measured from the month your SSDI benefits actually start, not from the month you filed your claim or received an approval notice. If you filed in January 2022 but your benefits were approved and began in April 2022, your 24-month period runs from April 2022 to March 2024, and Medicare begins April 1, 2024.

Social Security tracks this automatically. You will receive a notice in the mail about three months before your Medicare coverage date. This notice explains what coverage you are getting, what it costs, and how to decline if you choose to. Read it carefully, because it also tells you the exact date your coverage begins and what to do if you want to refuse.

If you have been on SSDI for 24 months and have not received a notice, contact Social Security directly. Call 1-800-772-1213 (TTY 1-800-325-0778) or visit your local Social Security office. Do not assume you are not enrolled—the notice may have been lost in the mail.

Why you might want to decline Medicare

The most common reason to decline Medicare is that you have employer health insurance through your own job or through a family member's employer. If your employer plan is still active and covers you, keeping that coverage instead of Medicare can make sense because employer plans often have lower out-of-pocket costs and broader networks than Medicare.

However, this situation requires careful planning. If you decline Medicare and later lose your employer coverage (because you stop working, your employer drops the plan, or you lose may be able to access), you cannot straightforward enroll in Medicare without penalty. You will owe a late-enrollment penalty on Part B for each full year you were not enrolled. The penalty is 10 percent of the Part B premium for each year of non-enrollment, and it is permanent—you pay it for the rest of your life.

Another reason some people decline is if they are covered by Veterans Affairs (VA) benefits or TRICARE (military family coverage). These programs can coordinate with Medicare, but the rules are complex. If you are in this situation, speak with your VA representative or TRICARE counselor before declining Medicare, because the interaction between these programs and Medicare affects what you will actually pay.

What happens if you refuse Medicare

Declining Medicare does not affect your SSDI payments. Your monthly benefit amount stays the same. You will not lose any other benefits or programs you are receiving, such as Medicaid (if you are enrolled in your state's program).

What changes is your healthcare coverage. You will not have Medicare Part A (hospital insurance) or Part B (medical insurance) unless you later enroll. If you need hospital care, emergency room services, or doctor visits, you will pay the full cost yourself unless you have another insurance plan covering you. This can be very expensive—a single hospitalization can cost tens of thousands of dollars.

If you have Medicaid in addition to SSDI, Medicaid will still cover some costs even if you decline Medicare. However, Medicaid programs vary by state, and not all states cover the same services. You should understand what your state's Medicaid covers before you decide to decline Medicare.

How to decline Medicare if you choose to

To refuse Medicare, you must contact Social Security in writing before your coverage date. A phone call or in-person visit is not enough—Social Security requires a written request. You can mail a letter to your local Social Security office, or you can visit in person and ask them to document your refusal on your record.

Your letter should state clearly that you are refusing Medicare Part A and Part B (or specify which parts you are refusing). Include your name, Social Security number, and the date you want the refusal to take effect. Keep a copy for your records.

If you miss the important date and Medicare enrolls you automatically, you have a limited window to unenroll. You can request to be removed from Medicare during the three months after your coverage begins (or within three months of receiving your Medicare card, whichever is later). After that window closes, you are enrolled until you actively request to disenroll, which you can do during the General Enrollment Period.

Re-enrolling after you decline: penalties and timing

If you decline Medicare and later want to enroll, you can do so during the General Enrollment Period, which runs January 1 through March 31 each year. Coverage would begin July 1 of that year. However, you will owe a late-enrollment penalty on Part B.

The late-enrollment penalty is 10 percent of the Part B premium for each full 12-month period you were not enrolled. If you declined for three years, you would owe 30 percent more than the standard Part B premium, and you would pay this higher amount for the rest of your life. Part A does not usually have a late-enrollment penalty if you enroll within a certain window, but the rules depend on whether you had other coverage.

There are some exceptions to the late-enrollment penalty. If you had creditable coverage (employer insurance, VA benefits, TRICARE, or certain other plans) during the time you were not enrolled in Medicare, you may not owe a penalty. You will need to prove you had that coverage, so keep documentation of any employer plans, VA letters, or other insurance you held.

Medicaid and Medicare coordination if you decline

If you are enrolled in Medicaid and decline Medicare, your Medicaid coverage continues. However, Medicaid's role changes depending on whether you later enroll in Medicare. While you are not on Medicare, Medicaid acts as your primary insurance for covered services. Once you enroll in Medicare, Medicare becomes primary, and Medicaid pays some costs Medicare does not cover (this is called "dual may be able to access" status).

Some states have programs that help people who are both SSDI beneficiaries and Medicaid recipients. These programs may offer additional support or services. Contact your state Medicaid office to understand what you are covered for if you decline Medicare.

Frequently Asked Questions

Can I decline Medicare Part A but keep Part B?

No. When you decline Medicare after SSDI, you are declining both Part A and Part B together. You cannot choose to keep one and refuse the other at the point of automatic enrollment. However, if you enroll later during the General Enrollment Period, you can enroll in Part A without Part B, though this is uncommon and usually not recommended.

What if I am still working when Medicare is supposed to start?

If you are working and have employer insurance, you can still decline Medicare. However, if you are working, you may lose SSDI benefits due to work incentive rules (your earnings may exceed the substantial gainful activity threshold). Speak with a work incentive counselor at your local Ticket to Work program before declining Medicare, because your work situation affects both your benefits and your healthcare options.

Does declining Medicare affect my family members' benefits?

No. Your decision to decline Medicare applies only to you. If family members are receiving benefits on your SSDI record (such as a spouse or child), their benefits and their Medicare enrollment are separate from yours.

Can I decline Medicare if I am under 65?

Yes. Age does not matter. If you are on SSDI and have been receiving benefits for 24 months, Medicare enrolls you regardless of your age. You can decline it at any age.

What if I want to decline but I am not sure if I should?

Contact your local Social Security office or call 1-800-772-1213 before your coverage date. You can also speak with a benefits counselor through your state's Work Incentive Planning and information (WIPA) program, which is free. They can review your specific situation and help you understand the long-term cost of declining versus enrolling.