How Tax Brackets Really Work: Marginal vs. Effective Tax Rate

Picture your taxable income as water poured into a stack of buckets. The first bucket is taxed at 10%. Once it is full, the overflow goes into the 12% bucket, then 22%, 24%, 32%, 35% and finally 37%. Seven rates exist today, and every taxpayer with enough income passes through the lower buckets first. A person earning $1 million pays exactly the same tax on their first dollars as a person earning $40,000.

Your marginal rate is the rate of the highest bucket your income reaches. It tells you how much tax you would pay on one additional dollar. Your effective rate is total tax divided by income, and it is always lower than the marginal rate because most of your income sat in cheaper buckets.

To keep the arithmetic readable, imagine a simplified schedule: 10% on the first $10,000, 12% on the next $30,000 and 22% on everything above $40,000. A single filer with $60,000 of taxable income would owe:

Marginal rate: 22%. Effective rate on taxable income: $9,000 ÷ $60,000 = 15%. For the exact current thresholds for your filing status, use our federal income tax calculator, which applies the published brackets automatically.

Brackets apply to taxable income, which is gross income minus pre-tax contributions (traditional 401(k), HSA, some health premiums) and minus either the standard deduction or your itemized deductions. That is why two people with the same salary can face different marginal rates: one contributes heavily to a 401(k), the other does not. It is also why the effective rate on your gross salary is lower still than the rate on taxable income.

Suppose a raise moves $2,000 of your income from the 12% bucket into the 22% bucket. Only those $2,000 are taxed at 22%, costing $440 in income tax instead of $240. You still keep the remaining $1,560 minus payroll taxes. There is no point at which earning one more dollar of wages causes you to lose more than a dollar to federal income tax.

The genuine exceptions are benefit cliffs, not brackets: certain credits, subsidies (such as ACA premium credits) or means-tested programs phase out as income rises, which can create high implicit marginal rates in narrow income ranges. Those are worth checking if you are near an eligibility limit, but they have nothing to do with the bracket table itself.

Social Security (6.2% for employees, up to the annual wage base) and Medicare (1.45%, plus an extra 0.9% above $200,000 for single filers) are not bracketed. They apply from the first dollar of wages. That is why low earners often pay more in FICA than in income tax. Self-employed people pay both halves, as explained in our self-employment tax guide.

Most states with a graduated income tax use the same layered logic, with their own thresholds. Others use a single flat rate, and nine states do not tax wages at all. Compare states with our no-income-tax states guide or the salary calculator by state.