What Your Employer Withholds and Why
Your employer removes taxes from each paycheck before you see the money. These withholdings cover federal income tax, Social Security tax (6.2 percent of your gross pay), and Medicare tax (1.45 percent of your gross pay). Some states and cities also withhold income tax. The amount withheld depends on what you told your employer on Form W-4 when you were hired, your income level, and your filing status.
The federal withholding is not a fixed percentage. It changes based on tax brackets, which shift each year. Your employer uses IRS tables and the information from your W-4 to calculate how much to hold back. If the calculation is wrong, you will either owe money at tax time or receive a refund.
Key Takeaways
- Federal income tax withholding is calculated using your W-4 form, your pay frequency, and IRS withholding tables that change yearly.
- Social Security and Medicare taxes are fixed percentages (6.2 percent and 1.45 percent) taken from every paycheck up to the Social Security wage base limit.
- State and local income taxes vary by location and are withheld separately from federal tax.
- You can estimate your annual tax withholding by multiplying your per-paycheck deduction by the number of pay periods in a year.
- If too much or too little is being withheld, you can submit a new W-4 to your employer to adjust future paychecks.
How Federal Income Tax Withholding Is Calculated
Your employer starts with your gross pay for that pay period. Gross pay is your salary or hourly wage before any deductions. The employer then subtracts any pre-tax deductions you have, such as contributions to a traditional 401(k) or health insurance premiums. This reduced amount is called taxable wages.
Next, your employer looks up the withholding amount using IRS Publication 15-T, which contains tables organized by filing status (single, married filing jointly, head of household, or married filing separately), pay frequency (weekly, biweekly, semimonthly, or monthly), and the number of allowances or adjustments you claimed on your W-4. The table tells your employer exactly how much federal tax to withhold.
The IRS updates these tables every year, and sometimes multiple times per year if tax law changes. Your employer is responsible for using the current tables. If your employer uses outdated tables, your withholding will be wrong.
Social Security and Medicare Tax Withholding
These two taxes are simpler than federal income tax because they are flat percentages. Social Security tax is 6.2 percent of your gross pay, and Medicare tax is 1.45 percent of your gross pay. Together they are called FICA taxes (Federal Insurance Contributions Act).
Social Security tax stops once you reach the wage base limit for that year. In 2024, that limit is $168,600, meaning no Social Security tax is withheld on income above that amount. Medicare tax has no wage base limit and continues on all income. If you earn over $200,000 (single) or $250,000 (married filing jointly), an additional 0.9 percent Medicare tax is withheld.
Your employer withholds these amounts automatically. You cannot reduce them by changing your W-4 or claiming deductions.
State and Local Income Tax Withholding
Forty-one states and many cities withhold income tax from paychecks. The calculation varies widely. Some states use a flat tax rate (the same percentage for all income levels), while others use tax brackets similar to the federal system. A few states have no income tax at all: Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, and Wyoming.
Your employer withholds state and local tax based on information you provide on state W-4 forms, which differ from the federal form. Some states use the same withholding method as the federal government; others do not. If you work in a state different from where you live, you may need to file returns in both places.
To find your state's withholding rules, search "[your state] income tax withholding" or contact your state's department of revenue.
Calculating Your Total Annual Withholding
To estimate how much tax will be withheld over a full year, multiply the amount withheld from one paycheck by the number of pay periods in a year. If you are paid biweekly (26 times per year) and $180 in federal tax is withheld each period, your annual federal withholding is $180 × 26 = $4,680.
Do the same for Social Security, Medicare, and state taxes. Add them together to get your total estimated annual withholding. This number helps you understand whether you are on track to owe money or receive a refund at tax time.
Keep in mind that this is an estimate. Your actual withholding may differ if your pay changes, you get a raise, you change your W-4, or you have other income sources such as a second job or freelance work.
When Your Withholding Is Wrong
If too much tax is withheld, you will receive a refund when you file your tax return. If too little is withheld, you will owe money. Neither outcome is ideal: a large refund means you gave the government an interest-free loan, and owing money means you may face penalties if you do not pay by the important date.
The most common reason for wrong withholding is an incorrect W-4. If you claimed too many allowances, too little will be withheld. If you claimed too few, too much will be withheld. Other reasons include a change in income, a second job, marriage, divorce, or a dependent child.
If you think your withholding is wrong, you can submit a new W-4 to your employer at any time. The new withholding will take effect on your next paycheck. The IRS website has a withholding calculator that can help you figure out what to claim.
Understanding Your Pay Stub
Your pay stub shows the breakdown of all withholdings. Look for these line items: gross pay (your total earnings before deductions), federal income tax withheld, Social Security tax withheld, Medicare tax withheld, and any state or local taxes. The remaining amount is your net pay, or take-home pay.
Your pay stub also shows year-to-date totals, which tell you how much has been withheld so far this year. This information is useful when you file your tax return, because it matches the amounts reported on your W-2 form.
If you notice an error on your pay stub—such as the wrong withholding amount or a missing deduction—report it to your payroll department when ready. Errors can affect your tax return.
Frequently Asked Questions
Can I stop taxes from being withheld from my paycheck?
No. Social Security and Medicare taxes are mandatory and cannot be stopped. Federal income tax withholding is also mandatory unless you meet very specific criteria (such as owing no tax the previous year and expecting to owe none this year). Even then, your employer may still withhold. You cannot claim "exempt" on your W-4 to avoid all withholding.
What does "allowances" on the W-4 mean?
Allowances are a way to tell your employer how much to withhold. More allowances mean less withholding; fewer allowances mean more withholding. The newer W-4 form (used since 2020) uses a different system based on income, deductions, and credits rather than allowances, but the concept is the same: you adjust the form to change how much is withheld.
Why is my withholding different from my coworker's if we earn the same salary?
Because your W-4 forms are different. Your coworker may have claimed different allowances, have a spouse with income, have more dependents, or have different deductions. Filing status also matters: a single person and a married person earning the same salary will have different withholding.
Do I get back the taxes withheld if I do not owe anything?
If your total withholding exceeds what you actually owe in taxes, you receive a refund. If your withholding equals what you owe, you break even. You only owe money if your withholding was too low. The amount withheld is not automatically returned; it is applied to your tax bill when you file your return.
How do I know if my employer is withholding the right amount?
Use the IRS withholding calculator on irs.gov. It asks about your income, filing status, dependents, and other factors, then tells you whether your current withholding is likely correct or if you should adjust your W-4. Run it once a year or whenever your life changes.