Medicare starts automatically after you receive SSDI payments for 24 months

If you are receiving Social Security Disability Insurance (SSDI), Medicare coverage begins on the 25th month of your SSDI payments. You do not need to do anything to start it — Social Security enrolls you automatically. This means that if you started receiving SSDI payments in January, your Medicare coverage would begin in January of the following year, two years later.

The 24-month waiting period is built into the SSDI program itself. It exists regardless of your age. Even if you are younger than 65, you will receive Medicare at the 25-month mark of your SSDI may be able to access, not when you turn 65.

Social Security sends you a notice about three months before your Medicare coverage begins. This notice tells you your Medicare number, explains what Part A and Part B cover, and describes your enrollment options. Keep this notice — you will need the information when you first use Medicare.

Key Takeaways

  • Medicare begins automatically on the 25th month of receiving SSDI, with no action required on your part.
  • The 24-month waiting period applies to everyone on SSDI, regardless of age.
  • Social Security sends you a notice three months before coverage starts, which includes your Medicare number and enrollment details.
  • Part A (hospital insurance) is automatic, but you must decide whether to enroll in Part B (medical insurance) when your coverage begins.
  • If you delay Part B enrollment without a valid reason, you may pay a higher premium for the rest of your life.

What happens during the 24-month waiting period

While you are waiting for Medicare to begin, you may have other health insurance options. Some people stay on Medicaid, which is a separate program run by your state. Others have coverage through a job, a family member's plan, or a marketplace plan. You can keep any of these while you wait for Medicare.

If you do not have health insurance during the waiting period, you can purchase a plan through Healthcare.gov or your state's marketplace. You may also be able to get Medicaid through your state — the rules vary by state, and some states have expanded Medicaid to cover more people with disabilities.

The waiting period does not mean you are uninsured by default. It means Medicare is not yet your primary coverage. You are responsible for finding coverage on your own until month 25.

Part A versus Part B: what you need to know

Part A is hospital insurance. It covers inpatient hospital stays, skilled nursing facility care, hospice, and some home health services. Part A enrollment is automatic — you do not have to do anything. You will have Part A coverage starting on the same day your Medicare begins.

Part B is medical insurance. It covers doctor visits, outpatient services, lab tests, and some preventive care. Part B is not automatic. When Social Security sends you your Medicare notice, you will need to decide whether to enroll in Part B. If you want Part B, you do nothing — you are enrolled automatically unless you decline it in writing. If you do not want it, you must tell Social Security or Medicare that you are declining.

Most people enroll in Part B when it becomes available. If you decline Part B and later change your mind, you can enroll during the General Enrollment Period (January 1 to March 31 each year), but your premium will be 10 percent higher for each year you delayed enrollment. This penalty is permanent.

The notice you will receive and what to do with it

About three months before your Medicare begins, Social Security mails you a notice titled "Your Medicare Coverage Will Start." This notice includes your Medicare number, the date your coverage begins, and information about Part A and Part B. It also explains how to contact Medicare if you have questions.

Read this notice carefully and keep it in a safe place. Your Medicare number is different from your Social Security number, and you will need it to schedule doctor appointments, fill prescriptions, and file claims. Some healthcare providers ask for it before your first visit.

If you do not receive a notice three months before your coverage date, contact Social Security at 1-800-772-1213 to confirm your Medicare enrollment. Do not wait until your coverage is supposed to start.

What to do when Medicare begins

When your Medicare coverage begins, you should get a Medicare card in the mail. This card shows your Medicare number, the type of coverage you have (Part A, Part B, or both), and the date coverage started. You will need to show this card to doctors and hospitals.

Before your first doctor visit, call ahead and tell them you now have Medicare. Some providers need advance notice to update their records. If you were seeing a doctor before Medicare started, confirm that they accept Medicare and that your visit will be covered under your new insurance.

If you have other insurance (such as Medicaid or a marketplace plan), tell your healthcare providers about all your coverage. Medicare coordinates with other insurance to determine what each plan pays. Having multiple forms of coverage can actually reduce your out-of-pocket costs.

What happens if you are already on Medicare before SSDI

If you were already receiving Medicare before you started SSDI — for example, because you are over 65 or have end-stage renal disease — nothing changes. Your existing Medicare coverage continues without interruption. The 24-month waiting period does not explore to you because you are already covered.

Your SSDI payments and your Medicare coverage are separate. Starting SSDI does not affect your Medicare, and your Medicare does not affect your SSDI payments. Both can run at the same time.

Frequently Asked Questions

Can I decline Medicare when it starts?

Yes, you can decline Part B by telling Social Security or Medicare in writing before your coverage date. Part A is automatic and cannot be declined. However, declining Part B may result in a permanent premium penalty if you enroll later, so consider carefully before declining.

What if I am still working when Medicare starts?

If you are working and have health insurance through your job, you can keep that coverage and also have Medicare. Medicare becomes your secondary insurance, meaning your employer plan pays first. You should still enroll in Part B to avoid the permanent penalty, even if you do not use it right away.

Do I have to pay for Medicare?

Part A is free for most people on SSDI. Part B has a monthly premium that is deducted from your SSDI payment. The premium amount changes each year. You will see the exact amount in your Medicare notice before coverage begins.

What if my SSDI is denied or stops?

If your SSDI ends, your Medicare coverage continues for at least eight and a half more months. After that, you can keep Medicare by paying the full premium yourself, or you may be able to switch to a different type of coverage. Contact Medicare at 1-800-MEDICARE if your SSDI ends.

Can I choose a Medicare Advantage plan instead of Original Medicare?

Yes. When your Medicare begins, you can enroll in a Medicare Advantage plan (Part C) instead of using Original Medicare (Part A and Part B). Medicare Advantage plans are offered by private insurance companies and often include prescription drug coverage. You have a limited time to make this choice, so review your options when you receive your Medicare notice.