How Are Social Security Disability (and SSI) Backpayments Calculated?

When you are awarded Social Security or SSI disability benefits, Social Security may owe you more than just your awarded monthly disability checks. How much disability income you are owed depends on different factors, including the type of disability benefits you are receiving and how long you were owed past benefits.

Types of Back Payments

Back payments are paid for the months between the date you applied for disability benefits and the date you were approved for benefits. Due to the number of people that are applying for disability benefits and the time it takes to process your application, there is usually a long delay between your disability application date and approval date. And for Social Security Disability Insurance (SSDI) benefits, there is five-month waiting period, so you are only eligible to receive back pay for any delay beyond the waiting period (see “When Payments Will Begin,” below, for further information).

Another type of back payment that may be available to individuals who are receiving SSDI benefits are retroactive benefits. Retroactive benefits are paid for the months between when you became disabled (your "disability onset date") and when you applied for Social Security Disability benefits. These are benefits that you were eligible for and would have received if you had applied for benefits earlier.

SSDI v. SSI Benefits

The type of back payments you are eligible for depends on the type of benefits you are receiving. Those who are disabled can receive SSD (benefits for those with enough work history) or SSI (benefits for those who are poor). It is possible for individuals to receive both benefits. Below is a chart to clarify what you receive under each program.

When Disability Payments Begin

For those who are receiving SSI benefits, payments will generally begin the first full month after you are approved for benefits. For example, if you are approved for SSI benefits on January 1^st, you can expect to begin receiving benefits on February 1^st. An exception to the above rule is if an individual is determined to be “presumptively disabled.” Those individuals can begin to receive benefits while their application is being processed.

For those who are receiving SSDI benefits, there are several factors that affect when your payments begin: your disability onset date, your application date, and the five-month waiting mandatory period for SSDI.

Onset date. Social Security will use the date you filed a disability application as your “alleged onset date.” If Social Security doesn't challenge this date, the date of application will become your “established onset date” (EOD). Your EOD is important because it is on that date that benefits can begin. (If you were disabled for a period of time before your application date, you may want to hire an SSDI attorney to help you challenge your established onset date, so that the onset date reflects when you actually became disabled and unable to work.)

Wait period. There is a mandatory wait period that is applied to SSDI claims. You must be disabled for five months after your disability onset date before you can start receiving SSDI cash payments. You will receive disability benefits starting at the beginning of the sixth month. The five-month wait period is generally shorter than the time it takes for an application to be approved, so the waiting period doesn't usually delay the start of your monthly payments. However, disability benefits will not be paid during the waiting period (meaning individuals will not get paid for five of the months of back payments).

Application date. Retroactive benefits generally may not be collected for more than 12 months. If you add this year of retroactive benefits to the five-month wait period, the farthest back that Social Security will recognize a disability onset date is 17 months before the application date (12 + 5 = 17). This is true even if you actually became disabled years ago.

Examples of Back Payment Calculations

By using the date your entitlement to payments should begin (discussed in the above section), you should be able to calculate the amount of your back pay. Here are some examples.

How Are Back Payments Made

If you are approved for SSDI only, you'll most likely receive one lump-sum payment for the entire amount of your backpayments.

If you are approved for SSI, or SSI and SSDI, the rules are different. Social Security generally pays the past-due benefits for SSI or combined SSI/SSDI in three equal installment payments that are separated by six months each. However, you are eligible for larger first and second installments if you need funds for necessities (housing, food, medical needs) or to pay off debts for necessities. Or, you may be eligible for one lump-sum payment if you are not expected to live past the next 12 months or you are no longer eligible for SSI benefits at the time you receive your backpay (and not expected to become eligible for benefits within the next 12 months). For more information, read our article on lump-sum payments of backpay.

To learn more about disability backpay in general, see Disability Secret's section on Social Security disability backpay.