Social Security Tax Calculator
This professional-grade tool estimates how much of your Social Security benefit is subject to U.S. federal income tax, following IRS Publication 915. It is designed for retirees, planners, and advisors who need a fast, accurate, and accessible calculation of taxable Social Security benefits.
Calculator
Results
Enter your information to see results. This estimator follows IRS Publication 915 thresholds and logic.
Authoritative Data, Methodology, and Guidance
Data Source and Methodology
Primary source: IRS Publication 915 — Social Security and Equivalent Railroad Retirement Benefits (most recent edition). See IRS: https://www.irs.gov/publications/p915. Complementary guidance: SSA — Taxes and Your Social Security Benefits: https://www.ssa.gov/benefits/retirement/planner/taxes.html.
Tutti i calcoli si basano rigorosamente sulle formule e sui dati forniti da questa fonte.
This calculator implements the standard IRS thresholds and the provisional income approach described in Publication 915. Dollar thresholds are not indexed for inflation and may be updated by IRS; always check the current publication.
The Formula Explained
PI = OI + TEI + 0.5\,\times\,SS
Single/HOH/QSS: (Base, Second) = (25{,}000,\ 34{,}000)
MFJ: (32{,}000,\ 44{,}000)
MFS lived with spouse: (0,\ 0) — if not lived with spouse, use Single thresholds.
Taxable SS (T) is piecewise:
T = \begin{cases} 0, & \text{if } PI \le B \\[4pt] \min\!\bigl(0.5\cdot(PI - B),\ 0.5\cdot SS\bigr), & \text{if } B < PI \le S \\[6pt] \min\!\bigl( 0.85\cdot(PI - S) + C,\ 0.85\cdot SS \bigr), & \text{if } PI > S \end{cases}
Glossary of Variables
How It Works: A Step-by-Step Example
Scenario: Filing status = Single; SS = $24,000; OI = $20,000; TEI = $0.
- Compute provisional income: PI = 20,000 + 0 + 0.5 × 24,000 = $32,000.
- Single thresholds: Base B = $25,000; Second S = $34,000. Since 32,000 is between B and S, use the middle rule.
- Taxable SS T = min(0.5 × (32,000 − 25,000), 0.5 × 24,000) = min(3,500, 12,000) = $3,500.
- Non‑taxable SS = 24,000 − 3,500 = $20,500. Taxable percentage ≈ 3,500 / 24,000 = 14.6%.
This demonstration mirrors the calculator's logic. Your situation may differ; consult a qualified tax professional for personalized advice.
Frequently Asked Questions (FAQ)
1) Is all Social Security taxable?
No. Depending on your provisional income and filing status, from 0% up to 85% of your Social Security benefits may be taxable.
2) What is counted as “other income”?
Wages, pensions, IRA/401(k) distributions, taxable interest/dividends, capital gains, rental and business income, and other taxable items. Do not include Social Security itself.
3) Why does tax‑exempt interest count?
Although excluded from taxable income, tax‑exempt interest is added to provisional income per IRS rules, which can increase the taxable portion of Social Security.
4) I file Married Filing Separately. How does that affect me?
If you lived with your spouse at any time during the year, the thresholds are $0 / $0, meaning up to 85% of benefits may become taxable quickly. If you did not live with your spouse, Single thresholds apply.
5) Does this compute my total tax bill?
No. It estimates the amount of Social Security included in taxable income. Your actual tax depends on deductions, credits, withholding, and other items.
6) Are state taxes included?
No. States vary widely. This tool covers U.S. federal rules only.
7) Will the thresholds change?
Historically, these dollar thresholds are not indexed for inflation. Always verify with the current IRS Publication 915.