What is RSDI? How is this different from SSI and SSDI?

Retirement, Survivors and Disability Insurance. An acronym for three types of benefits SSA pays. RSDI is considered “Social Security” benefits and individuals are insured by Medicare. SSI is Supplemental Security Income, which is for low income individuals with a disability. Individuals with SSI are insured by Medicaid. SSDI is Social Security Disability Insurance and is paid to disabled individuals who have paid into Social Security and earned their 40 quarters or equivalent.