How is Social Security Disability taxed?

Social security disability and social security benefits are the same thing and would be subject to income on your correctly completed 1040 income tax return When you have other sources of world wide income.

Generally, if Social Security benefits were your only income, your SSB benefits are not taxable and you probably do not need to file a federal income tax return.

If you have any other sources of worldwide income and (tax exempt interest and exempt dividends) then it is possible for some of your SSB to become taxable income on your income tax return and then you would be required to file an income tax return.