Q What is the difference between SSI and SSDI?
Social Security Disability Insurance (sometimes called SSDI) is a program designed to provide coverage to disabled workers. If you worked and paid into Social Security, then you may be eligible to apply for SSDI.
SSDI works like any other insurance policy. While you are working, the taxes you pay into Social Security are like the insurance premiums. Your coverage lasts for a period of years after you leave work, and then, like any other insurance policy, it lapses. To be eligible for benefits under this program, you must establish that you were disabled before your coverage under this program ended, or what Social Security calls your "date last insured."
If you have not worked enough during the relevant period, or did not pay into Social Security from your check, then you will not be eligible for SSDI. Some state and municipal employees participate in other pension and/or disability programs but do not pay into Social Security, and therefore may not be eligible for SSDI.
The second program, Supplemental Security Income (called SSI), is not based on your work history. Instead, this program is closely tied to income and asset limits. To be eligible for SSI, your household income and assets must be under the limits set by Social Security.
You may be eligible for one or both of these programs. To find out if you meet the requirements for one or both, you should call Social Security or go into the Social Security district office nearest you.