Many of us must pay federal income taxes on our Social Security benefits. This usually happens only if you have other substantial income in addition to our benefits (such as wages, self-employment, interest, dividends and other taxable income that must be reported on your tax return).
We will pay tax on only 85 percent of your Social Security benefits, based on Internal Revenue Service (IRS) rules. If you:
Your adjusted gross income+ Nontaxable interest+ ½ of your Social Security benefits= Your “combined income“
IRS Publication 915 Social Security and Equivalent Railroad Retirement Benefits