Your effective tax rate is the percentage of your income that actually goes to federal income tax once the brackets, deductions, and credits have all done their work. To calculate it, divide your total tax by your taxable income and multiply by 100. Both numbers sit on your Form 1040, and the math takes about thirty seconds. The result is almost always lower than the bracket rate you’d guess from a tax table, and it tells you far more about your real tax burden than any bracket label.
How to Calculate It From Your Form 1040
Two lines on Form 1040 give you everything you need.1Internal Revenue Service. About Form 1040, U.S. Individual Income Tax Return
- Line 15 is your taxable income: what’s left after you subtract either the standard deduction or your itemized deductions. This is the figure the IRS runs through the tax tables.
- Line 24 is your total tax. It includes income tax from the brackets plus self-employment tax, penalties on early retirement withdrawals, and other additions, minus certain nonrefundable credits. It’s your complete federal income tax liability for the year.2Internal Revenue Service. Form 1040, U.S. Individual Income Tax Return
The formula: (Line 24 ÷ Line 15) × 100 = your effective tax rate.
Some planners prefer to divide total tax by gross income or adjusted gross income instead. That version folds in the benefit of your deductions and shows what share of every dollar you earned actually went to the IRS. The Form 1040 method isolates how the bracket system itself treated the income that was subject to tax. Neither is wrong. The rest of this article uses the Form 1040 method because those numbers are right in front of you on your return.
A Worked Example
Say you’re a single filer who earned $75,000 in 2026. After claiming the standard deduction of $16,100, your taxable income is $58,900.3Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 The progressive brackets work through it in layers:
- 10% on the first $12,400: $1,240
- 12% on $12,401 to $50,400: $4,560
- 22% on $50,401 to $58,900: $1,870
Total federal income tax: $7,670. Divide that by taxable income of $58,900 and your effective tax rate is about 13%. Your marginal rate is 22%, but your effective rate is nearly ten percentage points lower because the bulk of your income was taxed at 10% and 12%.
If you use the gross income version instead, $7,670 ÷ $75,000 gives you roughly 10.2%. That’s lower because it also credits you for the $16,100 the standard deduction shielded from tax entirely.
Effective Rate vs. Marginal Rate
The federal income tax is progressive: your income gets split into layers, and each layer is taxed at a higher rate than the last. Your marginal rate is the percentage applied to your last dollar. Your effective rate is the blended average across all the layers. The two are never the same unless every dollar you earned fit inside the lowest bracket.
For 2026, the seven federal brackets for single filers run 10%, 12%, 22%, 24%, 32%, 35%, and 37%, with the 37% rate kicking in above $640,600.3Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 Someone in the top bracket doesn’t pay 37% on everything. Their first $12,400 is taxed at 10%, just like yours. Only the income above $640,600 sees 37%. A single filer with $700,000 in taxable income has a marginal rate of 37% but an effective rate closer to 28%.
Married couples filing jointly get wider brackets, so more of their income falls into the lower tiers. The joint 22% bracket, for example, covers taxable income from $100,801 to $211,400.3Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 That pulls the effective rate down further for couples with the same combined income as a single filer.
What Pulls Your Effective Rate Down
Deductions
Deductions reduce taxable income before the brackets touch it. For 2026, the standard deduction is $16,100 for single filers and $32,200 for married couples filing jointly.3Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026 A joint filer’s first $32,200 is effectively taxed at 0%. If your itemized deductions (mortgage interest, state and local taxes up to the cap, charitable contributions) exceed the standard amount, you can deduct the larger figure instead. Either way, deductions shrink the pool of income that faces taxation and pull the effective rate lower.
Tax Credits
Credits are more powerful than deductions because they cut your actual tax bill dollar for dollar rather than just shrinking taxable income. A $1,000 deduction saves you $1,000 multiplied by your marginal rate. A $1,000 credit saves you a flat $1,000 regardless of your bracket.
The Child Tax Credit is worth up to $2,200 per qualifying child under 17, with up to $1,700 refundable even if you owe no income tax.4Internal Revenue Service. Child Tax Credit Other common ones include the Earned Income Tax Credit, the American Opportunity Credit for education, and residential energy credits. Because credits come off Line 24 directly, they have a proportionally larger effect on your effective rate than deductions of the same dollar amount.
Preferential Rates on Investment Income
Long-term capital gains and qualified dividends are taxed at 0%, 15%, or 20% depending on your total taxable income.5Internal Revenue Service. Topic No. 409, Capital Gains and Losses If a meaningful share of your income comes from investments held longer than a year, those lower rates drag down your overall effective rate. A single filer in the 24% ordinary income bracket might pay only 15% on long-term gains, and the blend produces a lower effective rate than if the same income were wages.
Payroll Taxes Aren’t in the Formula
The Line 24 calculation captures federal income tax and self-employment tax, but not the payroll taxes taken from a regular paycheck. For most workers those are a bigger hit than income tax, so leaving them out understates your total federal tax burden.
Social Security tax takes 6.2% of wages up to $184,500 in 2026; earnings above that cap are exempt.6Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet Medicare tax adds 1.45% on all wages with no cap. That’s 7.65% off the top of every paycheck. Your employer pays a matching 7.65%. If you’re self-employed, you pay both halves: 12.4% Social Security plus 2.9% Medicare.7Social Security Administration. Contribution and Benefit Base
High earners also owe an Additional Medicare Tax of 0.9% on wages above $200,000 for single filers or $250,000 for married couples filing jointly. Those thresholds aren’t indexed to inflation.8Internal Revenue Service. Questions and Answers for the Additional Medicare Tax
To get a total effective federal rate, add Line 24 to the Social Security and Medicare taxes shown on your pay stubs (or the self-employment tax from Schedule SE), then divide by your gross income. For the $75,000 earner from earlier, payroll taxes run about $5,738, which nearly matches the $7,670 in income tax. Including them pushes the effective federal rate from about 10% of gross income to about 18%. That combined number is closer to what you actually feel.
What This Rate Doesn’t Cover
Your Line 24 effective rate is a federal individual income tax figure. It doesn’t include state income tax, which ranges from 0% in states without an income tax to over 13% in the highest-tax states. Add your state rate on top for a fuller picture of your income tax burden.
Corporations calculate an effective rate the same way in principle — total federal tax divided by total income — but they work from a flat federal corporate rate of 21% set by the Tax Cuts and Jobs Act in 2017, and their own deductions, credits, depreciation schedules, and loss carryforwards. A corporate effective rate isn’t comparable to an individual one and answers a different question.