PROVISIONAL INCOME

The income level that is used to determine if a taxpayer is liable for tax on his or her Social Security benefits, and by how much. Provisional income is calculated by making certain adjustments to the taxpayer's gross income.

The formula for determining provisional income is as follows:

Provisional income = gross income + tax-free interest + 50% of Social Security benefits + any tax-free fringe benefits and exclusions - adjustments to income (except for the student loan deduction, tuition and fees deduction or domestic production-activities deduction)