Your benefits begin the later of (a) 12 months before the date of application or (b) five full months after the date you were found to be disabled. This is the “date of entitlement” in your case. Many people ask why benefits don’t begin on the date they were found disabled. Social Security Disability benefits never begin on the date one is found disabled because of the waiting period of five full calendar months. Another rule limits payment of back benefits to 12 months before the date of the application.
If you are eligible for Supplemental Security Income or SSI benefits, Social Security will pay SSI from the first of the month after a claimant meets all requirements to get SSI. These requirements are:
(1) you file an application,
(2) you are disabled, and
(3) you meet the income and asset requirements of the program.
Your SSI benefits may also change beginning the first month you are eligible for Disability Insurance Benefits.