SSI, or Supplemental Security Income, is a needs-based program that provides a monthly check to persons who are blind, elderly, or have a disability. For disabled people who have never worked, or those who haven't worked enough in the recent years to qualify for SSDI (Social Security Disability Insurance), SSI may be the only program available to them. However, the SSI program is tough to qualify for financially, as it has very low income limits and asset limits.

How Much Does SSI Pay?

The monthly payment amount for the SSI program is based on the "federal benefit rate" (FBR). In 2016, the FBR is $733 per month for individuals and $1,100 for couples (and the FBR increases annually if there is a Social Security cost-of-living adjustment).

The FBR is the maximum federal monthly SSI payment. Income you receive during the month, minus certain exclusions, can be subtracted from your federal monthly SSI payment. Additionally, state money can be added to your federal monthly payment. In most states, there is a state supplement, which is added to the federal benefit payment. Every state except Arizona, Arkansas, Georgia, Mississippi, Oregon, Tennessee, Texas, and West Virginia adds money to the federal SSI payment. The amount of the state supplement varies between states, from $10 to $200, and also depends on whether you are single or married and whether you are living in a nursing home, assisted living, on your own, or with others. In California, the state supplement as of 2016 was $156.40 per month for individuals and $396.20 for couples.

Earned Income Exclusion

If you earn income, you are allowed to deduct a certain amount of the income before it gets subtracted from your SSI payment. You can subtract $65 of your earned income, plus another $20 for earned or unearned income, and then subtract half of the remainder—that is the amount you can deduct from your income. Only the remainder of the income will be subtracted from your SSI payment.

In-Kind Support and Maintenance

If you receive SSI benefits and someone provides you with shelter and/or food that you don’t pay for, the Social Security Administration (SSA) will count this as income and substract it from your SSI payment. In other words, it reduces your monthly SSI payment to account for this in-kind support and maintenance, since the SSA considers that you don't need the full SSI payment since you're receiving some food or shelter for free. 

Concurrent SSI and SSDI Benefits

For those applicants who receive a low SSDI payment, Supplemental Security Income does exactly what its name implies. It supplements. For example, if an approved disability claimant receives SSDI monthly benefits in the amount of $396, an SSI award could be used to guarantee that the claimant's total monthly benefits equal the minimum SSI amount, which is currently $733 per month. The SSDI recipient would receive an additional $337 in SSI to bring her total monthly benefits to $733, a sum equal to the full SSI monthly benefit amount.

Of course, this scenario will not happen in every such case. Because SSI has resource (asset) limits (currently, an individual cannot have more than $2,000 in disposable assets), many SSDI claimants will not be eligible to receive Supplemental Security Income, no matter how low their SSDI benefit amount is.