In almost every case where a claimant is awarded Social Security or SSI benefits based on disability, past due disability benefits, or disability "backpay," will also be received, back to when the disability application was filed, or sometimes even earlier. The reason for this is plain: Social Security disability claims take a long time to process.
How far back you will receive benefits for depends on three factors.
The first factor that will determine when your disability starts is when you applied for Social Security disability or SSI benefits. For Social Security disability benefits (otherwise known as SSD or SSDI), an applicant can receive benefits back to their date of application and also potentially be considered for retroactive benefits during the year prior to their application date. This year can be referred to as the retroactive period (this doesn't apply to SSI).
For disability based on SSI, an applicant may potentially receive benefits back to the first of month after which he or she filed the disability application.
Alternatively, if you have a "protective filing date" that's earlier than the date you filed your disability application, you can get get disability benefits going back to that date as if it were your application date. For more information, see our article on protective filing dates.
The second and more important factor regarding when a person's disability starts is the onset date of their disability— that is, when their disability began. When an SSDI claimant files an application for disability benefits, they indicate (on the application) when they think their disability began. This is known as the alleged onset date, or AOD.
A disability claimant who has been approved for benefits will be given an EOD, or "established" onset date. The established onset date is set by a DDS disability examiner, or an administrative law judge (if your case has gone to hearing), and is considered to be the date for when a claimant's disability actually began. The EOD will be based entirely on the claimant's medical records and work history. In other words, how far back an individual's disability is determined to have began will be decided according to the evidence available from the claimant's doctor's reports, lab results, and disability application.
For SSI, the date of disability is often before the application date, but the SSA won't set an EOD before the date of application (since SSI recipients can't get benefits before the month of application). In the case that the SSA says the EOD is after the application date, the SSI recipient would start to get benefits starting on the EOD rather than the month following the application.
For SSDI, whether or not benefits will be payable back to the beginning of the 12-month retroactive period time will depend on the onset date that is established, either by a disability examiner or by an administrative law judge. But there is another twist in calculating the SSDI starting date: a waiting period.
There is a third factor that applies to Social Security disability (SSDI) benefits (not to SSI awards). That third factor is the five-month waiting period.
Essentially, SSDI applicants who have been approved and given an established date of onset will have five months of benefits removed from the beginning of their disability. In other words, the "date of entitlement" doesn't start until five months after the EOD.
If the claims examiner or judge determines that the onset date is 17 months prior to the application date, or more, the claimant should be entitled to the entire 12 months of retroactive benefits prior to the date of the SSDI application.
All SSDI retroactive payments and backpay are paid as one lump sum. For SSI, small amounts of backpay (under a couple of thousand dollars) are paid in a lump sum, but larger amounts of backpay are usually split into three payments, six months apart. Learn more about when SSI backpay is paid in installments, and the exceptions to the rule.