What payroll taxes are and why they come out of your paycheck

Payroll taxes are the amounts your employer withholds from your paycheck and sends to federal and state governments on your behalf. They fund Social Security, Medicare, unemployment insurance, and income tax. Unlike a tip or a voluntary deduction, payroll taxes are required by law — your employer must take them out whether you want them to or not.

The money does not disappear. Federal income tax withholding goes toward your annual tax bill. Social Security and Medicare taxes fund those programs, and you build a record of contributions that affects your future benefits. Understanding how these are calculated helps you know what to expect on your paystub and whether your employer is withholding the right amount.

Key Takeaways

  • Social Security tax is 6.2% of your gross pay (up to a yearly cap), and Medicare tax is 1.45% with no cap, for a combined 7.65% that nearly all employees pay.
  • Federal income tax withholding depends on your W-4 form, which tells your employer how much to take based on your filing status, dependents, and other income.
  • State and local income taxes vary by where you live and work; some states have no income tax, while others withhold 3% to 10% or more.
  • Your paystub shows gross pay (before taxes), each tax withheld, and net pay (what you take home), so you can verify the math yourself.
  • If too much or too little is being withheld, you can adjust your W-4 at any time during the year, not just when you start a job.

How Social Security and Medicare taxes are calculated

Social Security tax is 6.2% of your gross pay, but only on earnings up to a cap that changes each year. In 2024, that cap is $168,600 — meaning once you earn that much in a calendar year, no more Social Security tax comes out. This is called the wage base. Your employer also pays 6.2%, so the total going to Social Security is 12.4%, but you only see your half on your paystub.

Medicare tax is 1.45% of your gross pay with no earnings cap — it keeps coming out no matter how much you make. Like Social Security, your employer pays an equal 1.45%. If your income is above a certain threshold (which depends on your filing status), an additional 0.9% Medicare tax may be withheld, bringing your total Medicare withholding to 2.35% on high earnings.

Together, Social Security and Medicare are often called FICA taxes (Federal Insurance Contributions Act). On a $1,000 paycheck, you would see roughly $62 for Social Security and $14.50 for Medicare withheld, totaling $76.50, before any federal or state income tax.

How federal income tax withholding works

Federal income tax withholding is not a flat percentage like Social Security and Medicare. Instead, it depends on information you provide on your W-4 form (officially the Employee's Withholding Certificate). When you start a job, you fill out a W-4 and tell your employer your filing status, how many dependents you have, whether you have other jobs or income, and whether you expect to owe or get a refund.

Your employer uses IRS tables and your W-4 answers to calculate how much federal income tax to withhold from each paycheck. If you claim zero dependents and say you are single, more comes out. If you claim dependents or say you are married, less comes out. The goal is to withhold roughly the right amount so that when you file your tax return in April, you do not owe a large bill or get a huge refund.

You can change your W-4 at any time — you do not have to wait until next year. If you got a big refund last year, you can adjust your W-4 to have less withheld and take home more pay now. If you owed money, you can increase withholding. Talk to your payroll or HR department about how to submit a new W-4.

State and local income tax withholding

Most states withhold income tax from your paycheck, but the rate and rules vary widely. Some states have no income tax at all (including Texas, Florida, and Wyoming), so nothing is withheld. Other states withhold between 3% and 10% or more, depending on your income level and filing status.

A few states and many cities also have local income taxes — Philadelphia, for example, withholds a local tax in addition to Pennsylvania state tax. When you start a job, you may fill out a state W-4 form (the name and format vary by state) that works similarly to the federal W-4. Some states use your federal W-4 information instead.

If you move to a new state or work in a state different from where you live, withholding can get complicated. You may need to file in multiple states or adjust your withholding. Your payroll department can tell you which state taxes explore to your situation.

Reading your paystub to verify the math

Your paystub (also called a pay stub or earnings statement) breaks down exactly what was withheld. It shows your gross pay (total earnings before any deductions), then lists each tax withheld separately: federal income tax, Social Security, Medicare, state income tax, and any local taxes. At the bottom is your net pay — the amount you actually receive.

To spot-check the math, take your gross pay and multiply by 0.062 for Social Security (if you have not hit the yearly cap). Multiply by 0.0145 for Medicare. These should roughly match what your paystub shows. Federal income tax is harder to verify without IRS tables, but if it looks drastically different from past paychecks, ask your payroll department why.

Your paystub also shows year-to-date totals, which tell you how much you have paid in taxes so far this year. This is useful when you file your tax return — you will need these numbers to report how much was withheld.

What to do if your withholding is wrong

If you consistently get a large refund every April, too much is being withheld. You can submit a new W-4 to reduce withholding and take home more pay each month. If you owe money every year, too little is being withheld, and you should increase withholding on a new W-4.

Life changes also affect withholding. If you get married, have a child, take a second job, or your spouse starts working, your withholding may need to adjust. The IRS provides a withholding calculator on its website (irs.gov) that can help you figure out what to claim on a new W-4.

Changing your W-4 takes effect on your next paycheck, so you do not have to wait long to see the difference. If you are unsure what to claim, your payroll or HR department can walk you through the form, or you can speak with a tax professional.

Self-employment and contractor taxes

If you are self-employed or work as an independent contractor (a 1099 contractor), you do not have an employer to withhold taxes. Instead, you are responsible for paying self-employment tax, which covers both the employee and employer portions of Social Security and Medicare — 15.3% total instead of 7.65%.

You also owe federal income tax on your net profit. Many self-employed people make quarterly estimated tax payments to the IRS rather than waiting until April. This is different from payroll withholding but serves the same purpose: spreading your tax bill throughout the year so you do not owe a large lump sum in April.

Self-employment taxes are more complex, and the rules depend on how much you earn and what kind of work you do. If you are new to self-employment, speaking with a tax professional or accountant can help you understand your obligations and avoid penalties.

Frequently Asked Questions

Why is my federal income tax withholding different from my coworker's if we make the same amount?

Your W-4 answers are different. If your coworker claims more dependents, is married, or has other income, their withholding will be lower. If they claim zero dependents or are single with no other income, their withholding will be higher. The same gross pay can result in very different net pay depending on W-4 choices.

Does my employer keep the taxes they withhold from my paycheck?

No. Your employer is required to send withheld taxes to the IRS and your state within a set timeframe (usually weekly or monthly). Your employer also pays their own matching portion of Social Security and Medicare. The withheld money is held in trust and remitted on your behalf.

What happens if my employer does not withhold taxes?

You are still responsible for paying the taxes owed, even if your employer fails to withhold. You could face penalties and interest. If you suspect your employer is not withholding or remitting taxes, you can report it to the IRS using Form 13909 or contact your state labor department.

Can I claim exempt from withholding to take home my whole paycheck?

You can claim exempt on your W-4, which stops federal income tax withholding, but only if you had no tax liability last year and expect none this year. Social Security and Medicare taxes still come out. Claiming exempt when you do not may have access to can result in owing a large bill and penalties when you file your return.

Do I get back the Social Security and Medicare taxes I pay?

Social Security and Medicare taxes fund those programs. You build a record of contributions that affects your future Social Security benefits and Medicare coverage. You do not get a refund of these taxes like you might with federal income tax withholding — they are ongoing program contributions.