Glossary
Provisional income (combined income)
The income figure the IRS uses to decide how much, if any, of your Social Security benefit is taxable.
Provisional income, which the Social Security Administration calls combined income, is the figure used to work out whether any of your Social Security benefit is taxed. It is your adjusted gross income, plus any tax-exempt interest, plus one half of the Social Security benefits you received for the year. That total is then measured against thresholds set in law, and depending on where it lands, either none, up to half, or up to 85 percent of your benefit may be counted as taxable income. Note what those percentages mean: they describe how much of the benefit is taxable, not the tax rate applied to it. This matters to you because only half your benefit counts toward the figure that decides how the other half is treated, and because the thresholds are not adjusted for inflation the way payments are. Money you take from a retirement account can therefore push more of your benefit into the taxable range in the same year.