Find how much of your Social Security is taxable using the IRS provisional income test.
How taxable social security benefits is worked out
Social Security is not automatically taxable. The IRS computes provisional income โ your other income plus tax-exempt interest plus half your benefits โ and compares it to two thresholds. Below the first, nothing is taxable; above the second, up to 85% is.
The 85% figure is a ceiling on how much of the benefit enters your taxable income, not a tax rate. The actual tax depends on your bracket, which is why the calculator applies your marginal rate separately.
How to fill it in
- Enter your annual Social Security benefits.
- Enter your other income and any tax-exempt interest.
- Choose your filing status and marginal rate.
The maths behind it
A worked example
Take the starting scenario, a marginal tax rate of 12%. That gives a taxable benefits of $11,300. Underneath, Provisional income comes out at $42,000 and First threshold at $25,000 โ exceeded. Change any field and every figure updates as you type.