What is Social Security?
Social Security is a federal insurance program created in 1935. You earn benefits by working and paying Social Security taxes from your paychecks. When you retire, become disabled, or pass away, you or your family members can receive monthly payments based on your earnings record. The amount you receive depends on how much you earned and for how long you worked.
What is SSI?
SSI stands for Supplemental Security Income. It is a needs-based program that gives monthly cash payments to people who have very limited income and resources. You do not need a work history to qualify for SSI. Instead, SSI helps elderly people age 65 and older, blind individuals, and disabled people (including children) who cannot support themselves financially.
Key Differences
The main difference is how you qualify. Social Security requires you to have worked and paid into the system. SSI does not require work history but does require you to be elderly, blind, or disabled and have low income and few resources. Social Security benefits are based on how much you earned, while SSI provides a set monthly amount to help cover basic needs. Some people can receive both Social Security and SSI at the same time.
Income and Resource Limits
SSI has strict limits on how much money and property you can own. For 2024, the monthly income limit for individuals is around $943 and for couples around $1,415. You can also own only limited resources, usually under $2,000 for individuals or $3,000 for couples. Social Security does not have income or resource limits. You can earn as much as you want and have as much savings as you want.
Who Can Receive Each
Social Security benefits go to workers who retire at age 62 or older, workers who become disabled, and family members of deceased or disabled workers. SSI goes to people age 65 or older with limited income, blind individuals of any age with limited income, and disabled people (including children) with limited income and resources. 
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