1. What Is SSDI Back Pay?

Back pay includes the benefits owed to you from:

• Your established onset date (EOD) – the date SSA determines your disability began
• Up to the date your claim is approved

Because the SSDI process often takes months or even years, these retroactive payments ensure you receive the benefits you were eligible for during that waiting time.

2. How Is Back Pay Calculated?

The SSA calculates back pay by:

• Identifying your EOD
• Applying the mandatory five-month waiting period (SSDI payments start only after five full months from your EOD)
• Counting the months between the end of the waiting period and the approval date

For example:
If SSA determines your disability began 12 months before your approval, you will receive 7 months of back pay after subtracting the five-month waiting period.

3. Retroactive Benefits

In addition to back pay, SSDI may also grant retroactive benefits, which cover:

• Up to 12 months before your application date if you were disabled during that time
• To qualify for retroactive benefits, you must prove your disability started before you applied, and you met SSDI work credit requirements during that period

4. How Back Pay Is Paid

Back pay is typically paid:

• As a lump sum, deposited directly into your bank account
• For those approved for both SSDI and SSI, your SSI back pay may be paid in installments instead

5. Factors Affecting Back Pay Amount

Your back pay amount depends on:

• Your date of disability onset as established by SSA
• When you filed your application
• The monthly SSDI benefit amount you are eligible to receive