Some people who receive Social Security have to pay federal income taxes on their benefits. It generally depends on how much other income you have, and it's based on a somewhat complicated formula Congress mandated many years ago.
You pay taxes on your benefits when your filing status is Single or Head of Household when your “combined income” – that is, your other income, plus half of your Social Security – is more than $25,000.
If you file a joint return, you must pay taxes when the combined income exceeds $32,000.
If you’re married and file a separate return, the amount is $0, and you’ll probably pay taxes on your benefits.
When you enter your SSA-1099 and all other income data into TurboTax, the program will calculate whether, and how much of, your Social Security income is taxable.
Below is a TurboTax FAQ which explains the computation is a bit more detail.
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