Can you please clarify "disability onset date" in regards to qualifying for Medicare? I became ill in 2016, hoped I would recover but did not, and filed for SSDI last December (2019). Even though Social Security agrees I was disabled since 2017, they say I can't get Medicare until the end of this year. I thought the two-year waiting period for Medicare started at the disability onset date, and not after you've received 24 payments? Can you please clarify, since I have incurred some medical bills that I cannot financially handle at this time?
Generally, the rule on Medicare eligibility for those who receive Social Security disability insurance (SSDI) is this: Eligibility for Medicare starts in the 25th month after you become eligible to receive SSDI payments. (Note there are two exceptions to the two-year Medicare waiting period: Those with end-stage renal disease or ALS can get Medicare benefits sooner.)
But when exactly do you become "eligible" to receive SSDI? Do you become eligible to receive benefits when your SSDI checks start getting deposited in your bank? Or as early as your disability onset date? Or as of your disability onset date plus five months, to make up for the SSDI waiting period?
Social Security calls the date you become eligible to receive SSDI payments your "entitlement date." Due to the five-month waiting period for SSDI, this date is five months after the date that Social Security establishes your disability began (your "established onset date," or EOD). You then count 24 months out from the entitlement date to see when you'll become eligible for Medicare. In other words, you can join Medicare 29 months after your established onset date.
In real life, it takes so long to get a disability hearing that applicants who go to the hearing stage of appeal to get benefits usually need to wait only a few months after their approval to be eligible for Medicare.
But what if your disability onset date was years ago, or 2017 as you say? Unfortunately, unless you applied for disability benefits a long time ago, this won't help you get Medicare benefits too much faster. If you didn't apply for Social Security disability until years after becoming disabled, or until 2019 in your case, your eligibility for Medicare won't start 29 months after the onset of your disability. Because of maximums set by federal law, your effective onset date can be no earlier than 17 months before the date you apply for Social Security benefits. For example, if you apply for benefits December 15, 2019, the earliest EOD you can receive is July 15, 2018.
In turn, this means your entitlement date can be only 12 months before you apply for SSDI, because of the five-month waiting period. (And Social Security will pay retroactive benefits for no more than 12 months prior to your application date.) This would mean the earliest date that your date of entitlement could be is December 15, 2018, and the earliest date you could be eligible for Medicare is December 15, 2020.
In essence, you can never become eligible for Medicare until at least one year has passed since you applied for Social Security disability. Moral of the story: If you think you'll need ongoing medical treatment and can't afford it, apply for Social Security soon after you become unable to work.
For more information about the complicated interaction between onset date, application date, and waiting periods, see Nolo's article on how Social Security calculates backpay.