Social Security Disability Insurance (SSDI) provides financial support if you are unable to work because of a serious medical condition.
After receiving 24 consecutive monthly SSDI payments, you become eligible for Medicare even if you aren’t yet 65 years old.
There is a five-month waiting period to begin receiving SSDI payments, but that doesn’t necessarily mean that someone applying for SSDI today must wait 29 months to begin Medicare coverage.
Being unable to work because of a disability can leave you feeling helpless, but help could be on the horizon. Time is of the essence when applying for Social Security Disability Insurance (SSDI) because there are waiting periods associated with receiving SSDI payments and, eventually, Medicare coverage.
For you to qualify for SSDI, which entitles you to monthly payments that can help keep you financially afloat during tough times, Social Security Administration (SSA) rules state that: 
- You must be incapable of working because of your medical condition.
- In the estimation of SSA, you are incapable of adjusting to other work in your condition.
- Your disability has lasted or could last at least one year or could result in death.
If you believe you qualify, you can apply online  or by calling the SSA at 1-800-772-1213.
To receive SSDI, you must have paid an appropriate amount of Social Security taxes through work based on your age. Your spouse’s work history won’t help you qualify, but your spouse’s earnings won’t be used against you when applying for SSDI. The more Social Security taxes you have paid, the larger your SSDI payments will be.
A decision about SSDI eligibility can take three to five months. You are not eligible for SSDI until the sixth full month after your disability started.  The decision process’s length will not impact your SSDI benefits unless it takes more than six months from when your disability began.
Once you start receiving SSDI payments, the clock starts ticking toward you being able to access Medicare for your health insurance coverage. After you receive Social Security disability benefits for 24 consecutive months, you become eligible for Medicare regardless of age.
While the two waiting periods mean you technically could be 29 months away from receiving Medicare benefits if you apply for SSDI today, the wait could be significantly shorter. Your waiting period factors your established onset date (EOD) instead of your application date. 
- Your EOD is the date that you became disabled based on the SSA’s findings.
- You can receive up to 12 months of retroactive SSDI payments based on your EOD.
- You will be eligible for Medicare 29 months after your EOD (assuming you’re still disabled).
- After your waiting period, Medicare enrollment is automatic, and you should receive your Medicare card in the mail about three months before coverage is set to begin.
What happens to my Medicare disability when I turn 65?
If you receive SSDI for 24 months and enroll in Medicare before turning 65, not much happens when you turn 65. You can remain on Medicare, but your eligibility technically is based on your age rather than your disability. You get the same Initial Enrollment Period surrounding your 65th birthday that everyone else gets, meaning you do have a chance to make changes to your coverage as you approach 65.
What is the difference between SSDI and SSI?
SSDI and SSI (Supplemental Security Income) are both disability-based programs but are not the same thing. While both use the Social Security Administration’s definition of a disability to determine eligibility, SSDI amounts consider an individual’s work history. In contrast, SSI considers limited financial resources, regardless of work history.
While those receiving SSDI are eligible for Medicare after receiving payments for 24 months, those applying for SSI apply for Medicaid simultaneously and are often simultaneously approved.  And while your spouse’s income doesn’t impact SSDI payments, a spouse’s income is among the financial resources that can reduce or even eliminate SSI payments. 
It is possible to receive both SSDI and SSI simultaneously, and SSI sometimes includes a “state supplement” not available to SSDI recipients. The SSA administers both forms of assistance.
Can I work with a disability and still get assistance?
It is possible to perform some work and still receive disability payments, but earnings are subject to a strict limit based on a Substantial Gainful Activity (SGA). A person able to earn a monthly amount over the SGA limit is considered capable of work and ineligible for SSDI. For 2021, the monthly SGA amount for non-blind persons is $1,310 and for blind persons is $2,190. The limits apply to non-blind persons on SSDI and SSI and blind persons on SSDI.
If you believe you are able to return to work but aren’t sure, the SSA allows for a “trial work period” during which you still can receive disability payments. The trial ends (and benefits end) if you’re able to earn more than $940 in a month for any nine months in a rolling 60-month period.