The US progressive tax system: marginal vs effective rates with 2025-2026 brackets. How standard deductions, itemizing, and credits change what you owe.
The United States uses a progressive income tax system, which means that as your income rises, the additional dollars are taxed at higher rates. The income scale is divided into brackets, and each bracket has its own rate that applies only to the portion of income that falls within that bracket — not to your entire income.
This is the single most misunderstood feature of the tax code. A common fear is that earning a bit more will "push you into a higher bracket" and leave you with less take-home pay. That is not how marginal taxation works. Only the income above a bracket threshold is taxed at the higher rate; the income below it continues to be taxed at the lower rates. Crossing into a new bracket can never reduce your total after-tax income.
Because of this structure, two people with the same marginal rate can owe very different amounts of tax, depending on how much of their income sits in the lower brackets. The bracket that applies to your last dollar earned is your marginal rate, but it is not the rate you pay on every dollar.
The marginal tax rate is the rate applied to your next dollar of taxable income — in other words, the rate of the highest bracket your income reaches. The effective tax rate is the average rate you actually pay across all your income. These two numbers are almost never the same, and the effective rate is always lower than the marginal rate.
Effective Tax Rate = Total Tax ÷ Taxable Income
Consider a single filer with $100,000 of taxable income in 2025. That income reaches the 22% bracket, so the marginal rate is 22%. But only the dollars above $48,475 are taxed at 22%; the rest are taxed at 10% and 12%. Adding up each layer produces a total tax of about $16,914, which makes the effective rate roughly 16.9% — well below the 22% marginal figure. This gap is exactly why a raise that bumps you into a higher bracket is rarely something to fear.
Knowing both rates is useful in different contexts. The marginal rate is what matters when you evaluate a raise, a side income, or a deductible contribution, because those items affect your top bracket. The effective rate is the better measure of your overall tax burden and is what people usually mean when they say "what percent of my income goes to tax."
Bracket thresholds are adjusted each year for inflation. The table below shows the 2025 federal income tax brackets for single filers, which are the figures most people are planning against during the current filing season. Married couples filing jointly have brackets that are roughly double these widths at the lower and middle levels.
| Tax rate | 2025 single-filer taxable income |
|---|---|
| 10% | $0 – $11,925 |
| 12% | $11,925 – $48,475 |
| 22% | $48,475 – $103,350 |
| 24% | $103,350 – $197,300 |
| 32% | $197,300 – $250,525 |
| 35% | $250,525 – $626,350 |
| 37% | $626,350 and above |
These brackets reflect the rates set by the Tax Cuts and Jobs Act of 2017. Several provisions of that law are scheduled to sunset after 2025, which means that without new legislation the 2026 brackets would revert to the pre-2018 structure, with rates of 10%, 15%, 25%, 28%, 33%, 35%, and a top rate of 39.6%, along with lower standard deductions. Tax planning for 2026 should account for this possibility, and the IRS publishes official inflation-adjusted figures each fall.
Your taxable income — the figure the brackets apply to — is not your gross income. Most filers first subtract either the standard deduction or their itemized deductions, whichever is larger. For 2025 the standard deduction is $15,000 for single filers, $22,500 for heads of household, and $30,000 for married couples filing jointly. Roughly nine in ten taxpayers now take the standard deduction rather than itemizing.
A deduction lowers your taxable income, so its value equals the deduction multiplied by your marginal rate. A credit, by contrast, lowers your tax bill directly, dollar for dollar, regardless of your bracket. A $1,000 deduction for someone in the 22% bracket saves $220 in tax; a $1,000 credit saves the full $1,000. This is why credits such as those for education, child care, and energy efficiency are considered far more valuable than an equal-sized deduction.
Common credits include the Child Tax Credit, the Earned Income Tax Credit, and education credits such as the American Opportunity Tax Credit, some of which are partially refundable — meaning they can reduce your tax below zero and produce a refund. Understanding which deductions and credits you qualify for, and whether they phase out at higher incomes, is often where the largest tax savings are found.
Effective Tax Rate Calculator — US, UK & EU
Put the numbers from this guide to work. The calculation runs entirely in your browser — nothing is sent to a server.