Social Security disability insurance (SSDI) is available to individuals who can no longer work due to an established disability (physical or mental). Only those who have paid taxes onto the Social Security system for at least several years are eligible for SSDI (see our article on SSDI eligibility to see how many work credits are required). Those who are approved for benefits receive monthly SSDI payments determined by their respective earnings records (the average amount is $1,171 in 2017).
The SSDI program does not put a limit on the amount of assets or unearned income you have (or income that your spouse may earn), unlike the low-income disability program, Supplemental Security Income (SSI).
However, the Social Security Administration (SSA) does put a limit on the amount of money that you can earn through work when you receive Social Security disability benefits, because if you can earn an income, you aren't considered disabled.
Specifically, if you can engage in what the Social Security Administration (SSA) calls "substantial gainful activity" (SGA), you won't be eligible for benefits. A person who earns more than a certain monthly amount is considered to be engaging in SGA. Federal regulations use the national average wage index to set the income limit for determining the SGA each year. In 2017, the amount is $1,170 for disabled applicants and $1,950 for blind applicants. The rules differ for business owners, since their monthly income may not reflect the work effort they put into their business.
While a disabled (nonblind) person applying for or receiving SSDI cannot earn more than $1,170 per month by working, a person collecting SSDI can have any amount of income from investments, interest, or a spouse's income.
It sometimes happens that people receiving SSDI improve and want to return to the workforce, but are afraid that they will be unable to keep a job due to their disabilities. To encourage disabled persons to try to return to work, the SSA provides for a trial work period. During the trial work period (TWP), a person receiving SSDI may have unlimited earnings and still receive full benefits without risking termination.
The trial work period provides that the person must provide services for at least nine months out of a rolling 60-month period before a disability is deemed to have ended. What counts as providing services? In 2017, any month in which earnings exceed $840 is considered a month of services for a person's trial work period. (Notice that this amount is different than the SGA amount.)
When the person has provided services for nine months, the SSA will evaluate the person's work to see if it has been over the SGA limits. If it is, disability benefits will continue for three months and then stop. But if this happens (SSDI benefits terminate because a person is working), benefits can resume within the next 36 months if the individual fails to earn the monthly SGA amount or becomes unable to work again due to the same disability.