Social Security Disability Insurance (SSDI) benefits are not impacted by unearned income. These benefits are based upon the worker's earnings history and taxes paid into the program. It is similar to a private disability insurance policy (i.e., Hartford, Aflac) in that paying your premiums entitles you to the disability coverage regardless of other unearned income or assets.
Supplemental Security Income (SSI), on the other hand, is a need-based disability program. It does not require any earnings history or taxes paid into the program; however, beneficiaries must have limited income and assets to be eligible.
If your husband is receiving only SSDI, there should be no change in his benefits.
If he is receiving only SSI and the inheritance exceeds the maximum allowable when added to your current assets, his benefits would be suspended until the assets are again less than the maximum allowable.
If he is receiving both SSDI and SSI and the inheritance exceeds the maximum allowable when added to your current assets, his SSI would be suspended until the assets are again less than the maximum allowable; however, the SSDI benefits would continue unchanged.
For married couples, the maximum allowable assets are $3000. Please see www.ssa.gov for the list of assets.
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