You don't explore for Medicare separately — it comes automatically with SSDI

When you start receiving Social Security Disability Insurance (SSDI), Medicare enrollment happens on its own schedule. You don't fill out a Medicare form or contact Medicare to request it. Instead, Social Security handles the enrollment after your SSDI claim is approved, and the timing depends on how long you've been receiving SSDI payments.

The key thing to understand is that Medicare may be able to access is tied to your SSDI start date, not to your age. Most people on SSDI become may be able to access for Medicare automatically after they've been receiving SSDI for 24 months. During those first 24 months, you may have other coverage options, which we'll cover below.

Social Security will send you a notice when Medicare enrollment is about to happen. You don't need to do anything to make it occur — but you do need to know when it's coming and what coverage you'll have.

Key Takeaways

  • Medicare enrollment happens automatically 24 months after your SSDI payments begin; you do not need to submit a separate form.
  • Social Security sends you a notice before Medicare starts, telling you which parts (Part A and Part B) you're enrolled in.
  • During the first 24 months of SSDI, you may be covered by Medicaid, employer insurance, or a spouse's plan instead of Medicare.
  • You can turn down Medicare Part B during the first enrollment window if you have other coverage, but doing so may cost you later.
  • Once Medicare starts, you pay premiums for Part B and possibly Part D (prescription drugs), though your SSDI payment may be reduced to cover them.

The 24-month waiting period before Medicare begins

The 24 months starts counting from the month your SSDI payments actually begin, not from the month you applied or were approved. If Social Security approves your claim in March but your first payment arrives in April, the 24-month clock starts in April.

During those 24 months, you need health coverage from somewhere. Many people on SSDI during this period are covered by Medicaid, which is a separate program run by your state. Medicaid rules vary by state — some states cover nearly everyone on SSDI automatically, while others require you to meet additional income or resource limits. You can contact your state Medicaid office or call 211 to find out what you're covered by right now.

If you have a job and employer health insurance, or if you're covered under a spouse's or parent's plan, you can keep that coverage during the 24-month wait. You don't have to switch to Medicare when it becomes available.

What happens when the 24 months are up

About two months before your 24-month mark, Social Security will mail you a notice. This notice tells you that Medicare Part A (hospital insurance) and Medicare Part B (medical insurance) will start on a specific date. Part A is automatic and has no premium. Part B has a monthly premium, which is usually deducted directly from your SSDI payment.

The notice also explains your options. If you have other health coverage that you want to keep, you can decline Part B during this window. However, if you turn down Part B and later lose your other coverage, you may face a late enrollment penalty — a permanent increase to your Part B premium. Because of this penalty, declining Part B is usually only a good choice if you're certain your other coverage will continue.

You do not need to do anything to accept Medicare Part A and Part B. If you receive the notice and do nothing, enrollment proceeds automatically.

Medicare Part D (prescription drug coverage) and when to enroll

Medicare Part D is optional coverage for prescription drugs. It is not automatic, and you have to make a choice about it. When your Medicare Part A and Part B start, you'll receive information about Part D plans available in your area.

You have a window of time to enroll in Part D without penalty — usually the same period when Part A and Part B start. If you don't enroll during this window and you don't have other drug coverage, you'll pay a late enrollment penalty each month for as long as you have Medicare. This penalty is permanent, so it's important to enroll or confirm you have other coverage.

If you're already taking prescription medications, compare the plans available to you and choose one that covers your drugs at the lowest cost. You can change plans once per year during the annual enrollment period (October 15 to December 7).

What your Medicare costs will be

Medicare Part A has no monthly premium for people on SSDI. Part B has a monthly premium that changes each year — in 2024, the standard premium is $164.90 per month, though higher-income beneficiaries pay more. This premium is usually taken directly out of your SSDI payment before you receive it.

Part D premiums vary depending on which plan you choose. Some plans cost as little as $5 to $10 per month, while others cost more. You also pay a deductible before coverage begins, and you share the cost of drugs with the plan (this is called cost-sharing).

If your income is very low, you may be covered by a program called Extra Help (also called the Low-Income Subsidy), which reduces or eliminates your Part D premium and cost-sharing. You can learn whether you may have access to by contacting Social Security or Medicare directly.

What to do if you disagree with your Medicare enrollment

If you receive a notice about Medicare enrollment and believe it contains an error — for example, if the start date is wrong or if you believe you shouldn't be enrolled yet — contact Social Security right away. You have a limited time to request a correction before enrollment takes effect.

You can reach Social Security by calling 1-800-772-1213 (TTY 1-800-325-0778), visiting your local Social Security office, or creating an account at ssa.gov. Have your Social Security number and the notice in front of you when you call.

If you've already been enrolled in Medicare and want to make changes — such as switching Part D plans or disenrolling from Part B — you can do so during specific enrollment periods. Medicare's annual enrollment period runs from October 15 to December 7 each year.

Coordinating Medicare with other coverage you might have

If you're still working or have coverage through a spouse's employer, you may have both Medicare and group health insurance at the same time. In this situation, one plan is "primary" (pays first) and the other is "secondary" (pays what's left). The rules for which is primary depend on your age, whether you're still working, and the type of coverage you have.

If you have Medicaid and Medicare at the same time (called "dual coverage"), Medicaid can help pay your Medicare premiums and cost-sharing. This is especially valuable if your income is very low. Your state Medicaid office can explain how the two programs work together in your situation.

If you're unsure how your coverage works or which plan should pay first, contact Medicare at 1-800-MEDICARE (1-800-633-4227) or your state Medicaid office.

Frequently Asked Questions

What if I'm still working when Medicare starts — do I have to take it?

You can decline Medicare Part B if you have health insurance through your job, but you must enroll in Part A (hospital insurance). If you turn down Part B and later leave your job, you'll have a window to enroll without penalty — but only if you enroll within eight months of losing your work coverage. After that, you'll face a late enrollment penalty.

Can I change my mind about Medicare Part D after I enroll?

Yes, but only during specific times. You can switch Part D plans once per year during the annual enrollment period (October 15 to December 7). If you made a mistake when you first enrolled, you may be able to change your plan within the first two months of enrollment. Contact Medicare to ask about your specific situation.

What happens to my Medicaid when Medicare starts?

This depends on your state. In some states, Medicaid ends when Medicare begins. In others, you can keep both (dual coverage). Contact your state Medicaid office to find out what will happen in your case. If you lose Medicaid, you may be able to enroll in a Medicare Savings Program, which helps pay your Medicare premiums.

Do I have to pay for Medicare if I'm on SSDI?

Part A is free. Part B and Part D have monthly premiums, which are usually deducted from your SSDI payment. If your income is very low, you may may have access to for Extra Help, which reduces or eliminates these costs. Contact Social Security or Medicare to learn whether you may have access to.

What if Social Security made a mistake about when my 24 months are up?

Contact Social Security when ready. Call 1-800-772-1213, visit your local office, or log into your account at ssa.gov. Bring your SSDI approval notice and any notices about Medicare enrollment. Social Security can correct the date if an error was made.