My wife and I filed jointly, our only income was my retirement, why is our social security taxable

[daviddavydmx]

Do I have to claim our social security on our taxes?

[JohnW15]

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.

https://ttlc.intuit.com/replies/3299920