How U.S. Tax Brackets Work: Marginal Rates Explained (2025)

The one idea that clears up most confusion

The single most common myth about federal income tax is that moving into a higher bracket taxes all of your income at the higher rate. It does not. The United States uses a progressive, marginal system: your income is sliced into bands, and each band is taxed only at its own rate. A raise that pushes part of your income into the 24% band does not suddenly tax your whole salary at 24% — only the dollars that fall inside that band are taxed at 24%.

According to the IRS — Federal income tax rates and brackets, there are seven federal rates for individuals: 10%, 12%, 22%, 24%, 32%, 35%, and 37%. The dollar thresholds for each rate change every year for inflation and depend on your filing status.

The 2025 bracket thresholds (returns filed in 2026)

The IRS publishes the inflation-adjusted figures each autumn. For tax year 2025, the IRS — Tax inflation adjustments for tax year 2025 set the top 37% rate to begin above $626,350 for single filers and $751,600 for married couples filing jointly. The standard deduction for 2025 rose to $15,000 for single filers and $30,000 for married filing jointly, which is the amount most households subtract before any brackets apply.

Because the standard deduction comes off the top first, two people with identical gross pay can land in different brackets depending on deductions, retirement contributions, and filing status.

A worked example

Suppose a single filer has $70,000 of taxable income in 2025. The first slice is taxed at 10%, the next at 12%, and the remainder at 22%. Only the top slice touches 22% — the effective (average) rate ends up well below 22%. That gap between marginal and effective rate is why a bonus is never “taxed away.” You always keep the majority of every extra dollar.

Where the marginal rate actually changes decisions

Your marginal rate is the right number for forward-looking choices: whether a traditional or Roth retirement contribution saves more, how much a deduction is worth (a $1,000 deduction saves $220 at a 22% marginal rate, not $1,000), and whether to defer income into a lower-earning year. Your effective rate is the right number for understanding your overall burden.

A short, practical checklist

• Find your taxable income (gross income minus the standard or itemized deduction), not your gross pay.
• Identify your filing status — thresholds differ sharply between single and joint filers.
• Use the marginal rate to value deductions and credits, and the effective rate to gauge your total bill.
• Confirm current figures against the IRS — Federal income tax rates and brackets before making decisions.