Income tax is money the federal government and most states take from your paycheck or earnings

Income tax is a percentage of the money you earn that goes to the federal government, and in most states, to your state government as well. The amount depends on how much you earned that year and your filing status. Unlike sales tax, which you pay when you buy something, income tax is taken from your wages before you see the money, or you pay it when you file your tax return.

The federal government uses income tax to fund programs like Social Security, Medicare, roads, and the military. States use their share for schools, police, and local services. The tax rate is not the same for everyone — the more you earn, the higher the percentage you typically pay. This is called a progressive tax system.

Key Takeaways

  • Income tax is a percentage of your earnings that goes to federal and state governments, taken either from your paycheck or paid when you file your return.
  • Tax rates increase as your income increases, so someone earning $30,000 pays a lower percentage than someone earning $100,000.
  • You only pay income tax on money above a certain threshold called the standard deduction, which changes each year and depends on your age and filing status.
  • Your employer withholds income tax from each paycheck based on a form you fill out called a W-4, and you settle the actual amount owed when you file your return.
  • Self-employed people and those with investment income must pay income tax directly, usually four times a year in estimated tax payments.

How tax brackets work and why earning more does not mean paying more tax overall

The federal government divides income into tax brackets — ranges of income that are taxed at different rates. In 2024, for example, a single person might pay 10 percent on the first $11,600 they earn, then 12 percent on earnings between $11,601 and $47,150, then 22 percent on earnings above that. The key point: you do not pay the highest rate on all your income, only on the portion that falls in each bracket.

This means earning an extra $1,000 does not suddenly make your entire paycheck taxed at a higher rate. Only that extra $1,000 is taxed at the higher bracket rate. Many people worry that a raise will push them into a higher tax bracket and leave them worse off — this does not happen. You always come out ahead with more income, even if a portion of it is taxed at a higher rate.

Tax brackets change every year because they are adjusted for inflation. The IRS publishes new brackets in October or November for the following year. Your state may have its own bracket system, which also changes annually.

The standard deduction means you do not pay tax on all your income

Before any tax is calculated, you get to subtract a set amount from your total income. This is called the standard deduction. For 2024, the standard deduction is $14,600 for a single person, $29,200 for married couples filing jointly, and $21,900 for heads of household. If your total income is below these amounts, you owe no federal income tax.

The standard deduction increases each year. It also depends on your age — if you are 65 or older, you get an additional deduction. This means an older person can earn more money before owing any tax. The standard deduction is separate from state income tax deductions, which vary by state.

Some people instead use itemized deductions, which means listing out specific expenses like mortgage interest, property taxes, or charitable donations. You choose whichever method gives you the larger deduction. Most people use the standard deduction because it is simpler and often larger.

Withholding is how your employer takes tax from your paycheck before you receive it

When you start a job, you fill out a W-4 form that tells your employer how much income tax to remove from each paycheck. Your employer sends that money to the IRS on your behalf. This is called withholding. At the end of the year, when you file your tax return, you find out whether your employer withheld the right amount.

If too much was withheld, you get a refund. If too little was withheld, you owe money when you file. The goal is to get as close as possible to zero — you do not want to give the government an interest-free loan all year, and you do not want to owe a large bill in April. You can adjust your W-4 anytime your situation changes, such as getting married, having a child, or taking a second job.

The W-4 asks about your filing status, number of dependents, and other income sources. It does not ask for your actual tax bracket — your employer uses IRS tables to calculate the withholding based on your answers. If you are unsure how to fill it out, the IRS website has a withholding calculator.

Self-employed people and investors pay income tax differently

If you are self-employed or have significant investment income, no employer is withholding tax for you. Instead, you must pay estimated tax four times a year — in April, June, September, and January. You calculate what you expect to earn, figure out the tax owed, and send it to the IRS on those dates. If you do not pay enough, you may owe a penalty when you file your return.

Self-employed people also pay self-employment tax, which covers Social Security and Medicare. This is in addition to income tax. The self-employment tax rate is 15.3 percent on 92.35 percent of your net earnings. You can deduct half of this amount from your income tax, which reduces your overall tax burden slightly.

Investment income — from stocks, bonds, rental property, or capital gains — is also subject to income tax. Long-term capital gains (profits from selling something you owned for more than a year) are often taxed at lower rates than regular income. Short-term gains are taxed like regular income.

State income tax varies widely and some states have none

Nine states have no state income tax: Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, Wyoming, and New Hampshire (which taxes only investment income). The remaining 41 states and Washington, D.C., collect income tax. State tax rates range from about 1 percent to over 13 percent, depending on the state and your income level.

Some states use a flat tax rate — everyone pays the same percentage regardless of income. Others use brackets similar to the federal system. A few states tax only certain types of income, like wages or investment earnings. Your state tax return is filed separately from your federal return, usually at the same time.

If you move to a new state during the year, you may owe tax to both states for the portion of the year you lived in each. Some states offer credits to prevent you from paying tax twice on the same income. Check your state's tax authority website for rules specific to your situation.

Tax credits and deductions reduce the amount of tax you owe

A tax deduction reduces your income before tax is calculated. If you earn $50,000 and have a $5,000 deduction, you pay tax on $45,000 instead. A tax credit reduces your tax bill directly. A $1,000 credit means you owe $1,000 less in tax, regardless of your income. Credits are generally more valuable because they reduce the actual tax owed, not just the income that is taxed.

Common deductions include the standard deduction, mortgage interest, student loan interest, and charitable donations. Common credits include the Earned Income Tax Credit (EITC) for lower-income workers, the Child Tax Credit for parents, and education credits for students. You do not have to choose between a deduction and a credit — you can use both if you may have access to for them.

Some credits are refundable, meaning if the credit is larger than your tax bill, you get the difference as a refund. The EITC and Child Tax Credit are partially refundable. Other credits are non-refundable, meaning they can only reduce your tax to zero but cannot create a refund.

Frequently Asked Questions

Why do I owe money at tax time if my employer was taking tax from my paycheck?

Your employer withholds based on the W-4 form you filled out, which uses estimates. If your actual tax situation is different — such as having a spouse with income, receiving a large bonus, or having investment income — the withholding may not match what you actually owe. You can adjust your W-4 anytime to change future withholding.

Do I have to pay income tax if I earn very little?

No. If your income is below the standard deduction for your filing status, you owe no federal income tax. For 2024, a single person earning less than $14,600 does not owe federal tax. However, you may still want to file a return to claim refundable credits like the EITC, which can result in a refund even if you owe no tax.

What is the difference between gross income and taxable income?

Gross income is all the money you earned before any deductions. Taxable income is what remains after you subtract the standard deduction (or itemized deductions) and certain other deductions. Tax is calculated on your taxable income, not your gross income. This is why earning $50,000 gross does not mean you pay tax on the full $50,000.

Can I reduce my income tax by contributing to a retirement account?

Yes. Contributions to a traditional 401(k) or traditional IRA reduce your taxable income for the year you make them. If you contribute $7,000 to a traditional IRA, your taxable income drops by $7,000, which lowers your tax bill. Contributions to a Roth IRA do not reduce your current tax bill but grow tax-free and can be withdrawn tax-free in retirement.

What happens if I do not file a tax return?

If you owe tax and do not file, the IRS will eventually contact you and charge penalties and interest on the unpaid amount. If you are owed a refund and do not file, you simply do not get the money — there is no penalty, but you lose the refund. The IRS generally has three years to collect taxes owed, though this can be longer if fraud is involved.