What Gets Taken Out of Your Paycheck
Your take-home pay is what's left after your employer withholds taxes and other deductions from your gross salary. The amount withheld depends on your filing status, how many dependents you claim, and your total income for the year. Federal income tax, Social Security tax (6.2%), and Medicare tax (1.45%) come out of every paycheck. Many states and some cities also withhold income tax.
Your employer uses a form called the W-4 to determine how much federal tax to withhold. When you start a job, you fill out a W-4 and tell your employer your filing status (single, married, head of household) and how many dependents you have. The more dependents you claim, the less tax your employer withholds. If you claim too few, you'll owe money at tax time. If you claim too many, you'll get a refund but have less money in each paycheck.
You may also have voluntary deductions: health insurance premiums, retirement contributions (like a 401(k)), or flexible spending accounts. These come out before federal income tax is calculated, which lowers your taxable income.
Key Takeaways
- Your W-4 form tells your employer how much federal tax to withhold based on your filing status and dependents.
- Federal income tax, Social Security tax (6.2%), and Medicare tax (1.45%) are withheld from every paycheck, plus any state or local income tax.
- Pre-tax deductions like 401(k) contributions and health insurance lower the amount of your salary that gets taxed.
- You can estimate your take-home pay by starting with your gross salary, subtracting pre-tax deductions, then explore federal and state tax rates based on your W-4 choices.
How to Calculate Federal Income Tax Withholding
The IRS publishes tax withholding tables that your employer uses to calculate how much to withhold from each paycheck. The amount depends on your pay frequency (weekly, biweekly, monthly), your filing status, and the number of allowances you claimed on your W-4. If you're paid biweekly and claim one dependent, your withholding will be different from someone who claims zero dependents.
You don't need to do this calculation yourself—your payroll department does it automatically. But you can see the withholding tables on the IRS website under Publication 15-T if you want to verify the math. The tables change each year because tax brackets adjust for inflation.
If your situation changes during the year—you get married, have a child, or take a second job—you should file a new W-4. Your employer will adjust your withholding starting with the next paycheck. You can also adjust your withholding if you expect to owe money or get a large refund at tax time.
Estimating Your Take-Home Pay
To estimate what you'll actually receive, start with your gross salary and work through the deductions in order. First, subtract any pre-tax deductions: 401(k) contributions, health insurance premiums, dependent care accounts, or transit benefits. These reduce your taxable income.
Next, calculate your federal income tax withholding using your filing status and W-4 allowances. Then subtract Social Security tax (6.2% of gross pay, up to a yearly cap) and Medicare tax (1.45% of all gross pay). Finally, subtract any state or local income tax if you live in a state that has it. What remains is your net pay—the amount that actually hits your bank account.
Here's a concrete example: If you earn $3,000 biweekly, contribute $400 to your 401(k), and claim married filing jointly with two dependents on your W-4, your federal withholding might be around $240. Social Security would be $186, Medicare would be $43.50, and if you live in a state with 5% income tax, that's another $130. Your take-home would be roughly $2,000.50 per paycheck. Your actual numbers will depend on your specific situation.
Understanding Your Pay Stub
Your pay stub shows exactly what was withheld and why. It lists your gross pay, each deduction (pre-tax and post-tax), your net pay, and year-to-date totals. The year-to-date numbers are important because some taxes have annual caps. Social Security tax, for example, stops being withheld once you've earned $168,600 in a year (the 2024 cap—this changes annually).
Check your pay stub each time you receive it. If the withholding looks wrong, compare it to the IRS withholding tables or use the IRS Tax Withholding Estimator tool on the IRS website. If something doesn't match, contact your payroll department. Errors happen, and catching them early means you can file a corrected W-4 before the end of the year.
Your pay stub also shows whether you're on track to owe or receive a refund. If you're consistently having large amounts withheld, you might adjust your W-4 to increase your take-home pay. If you're having too little withheld, you could adjust it the other way—though be careful not to underpay and face a penalty.
State and Local Income Tax
Nine states have no income tax: Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, Wyoming, and New Hampshire (which taxes only dividends and interest). If you live in any other state, your employer will withhold state income tax based on a state W-4 form you fill out when hired.
Some cities also impose local income tax. New York City, Philadelphia, and Columbus, Ohio are examples. If you work in one of these cities, your employer withholds local tax in addition to federal and state. The rate varies by location—it might be 1% to 3.5% of your gross pay.
If you work in one state but live in another, the rules get complicated. Generally, you pay tax to the state where you work, though some states have reciprocal agreements. If this applies to you, ask your payroll department which state's tax form to fill out.
Adjusting Your Withholding During the Year
You don't have to wait until next January to change your W-4. If you realize you're having too much or too little withheld, you can file a new W-4 at any time. Your employer will adjust your withholding starting with the next paycheck.
Common reasons to adjust: you got married or divorced, had a child, took a second job, or your spouse started working. You might also adjust if you're self-employed on the side and expect to owe taxes, or if you had a large refund last year and want more money in each paycheck instead.
The IRS Tax Withholding Estimator can help you figure out whether your current withholding is on track. It asks about your income, filing status, dependents, and other income sources, then tells you whether you should adjust your W-4. You can access it free on the IRS website.
What Happens at Tax Time
In January, your employer sends you a W-2 form showing your total gross pay for the year and all taxes withheld. You use this form to file your tax return. If the total withheld is more than you actually owe, you get a refund. If it's less, you owe the difference.
Your actual tax liability depends on your total income, filing status, and deductions. The amount withheld throughout the year is just an estimate. If you had a major life change—marriage, job loss, significant income increase—your withholding might not match your actual tax bill.
If you consistently get large refunds, you're having too much withheld and should adjust your W-4 to get more money in each paycheck. If you consistently owe, you're not having enough withheld and should adjust the other way. The goal is to have your withholding match your actual tax liability as closely as possible.
Frequently Asked Questions
What's the difference between gross pay and net pay?
Gross pay is your total salary before any deductions. Net pay is what you actually receive after taxes and other deductions are taken out. If you earn $50,000 a year gross, your net might be around $38,000 to $40,000 depending on your deductions and tax situation.
Can I claim zero dependents to get a bigger paycheck?
Yes, but you'll owe money at tax time. Claiming zero dependents means your employer withholds more federal tax from each paycheck, leaving you with less take-home pay. At tax time, you'll likely get a refund because you overpaid. If you need more money now, claiming dependents you're may have access to to is the right approach.
Why does my paycheck vary if my salary is the same?
Paychecks can vary because of overtime, bonuses, unpaid time off, or changes in pre-tax deductions. Some months you might contribute more to your 401(k) or have different health insurance costs. Also, if you're paid biweekly, some months have three paychecks instead of two, which affects your year-to-date totals and can shift your tax withholding slightly.
Do I have to fill out a W-4 every year?
No. Your W-4 stays in effect until you change it. However, the IRS recommends reviewing it each year, especially after major life changes or if you had a large refund or owed money. You can file a new W-4 whenever your situation changes.
What if my employer withheld the wrong amount?
Check your pay stub against the IRS withholding tables to verify. If there's an error, contact your payroll department when ready. They can file a corrected W-4 and adjust future paychecks. If the error affected multiple paychecks, your employer may issue a corrected W-2 at year-end, or you can claim the adjustment when you file your tax return.