Tax withholding, also known as withholding tax, is the amount of money your employer preemptively redirects on your behalf from your earned income to federal, state, and local governments. Because the federal government, most states, and some local governments tax workers’ income, tax withholding allows you to spread out your tax payments over the year. The alternative is estimated quarterly tax payments.
Why are taxes withheld from your paycheck?
The US income tax system is pay-as-you-go, meaning you pay taxes on most of your income as you earn it to support governmental services like Social Security and Medicare, public education, law enforcement, and federal agencies, to name a few.
For those working for a company that required you to fill out a W-4 form, your employer handles withholding the taxes you’re expected to owe. These taxes are then reported on a Form W-2 for you at the end of the year that you should use when completing your tax return. If you don’t have an employer that does this for you—for example, if you’re a freelancer or contract worker—you may be responsible for paying estimated taxes quarterly.
Not only can tax withholding prevent you from having to pay estimated taxes quarterly, but it also can help you avoid penalties and interest payments for paying too little in taxes earlier in the year.
What is federal tax withholding?
The amount you may have withheld for federal taxes from each paycheck is based on the total amount you’re expected to owe in federal taxes (think: income, Social Security, and Medicare taxes), as well as how you answer questions on your W-4.
Federal income tax
Your federal income tax withholding primarily depends on your filing status and on what tax bracket your income places you in. For tax year 2026, federal income tax brackets range from 10% to 37%, with higher incomes paying increasingly larger percentages. (If you need a refresher on how tax brackets work, check out our guide.) Other factors like income earned from another job or your investments, deductions, and credits impact your federal income tax withholding as well.
Social Security and Medicare taxes (aka FICA)
Social Security and Medicare taxes withheld are usually listed together as FICA, which stands for Federal Insurance Contributions Act, on your pay stub. Your Social Security tax—sometimes labeled OASDI for Old-Age, Survivors, and Disability Insurance—withholds 6.2% of all of your income up to $176,100 for income earned in 2025, and up to $184,500 for income earned in 2026.
Medicare tax withholding is set at a flat rate of 1.45% of your income with no ceiling. However, if you earn more than $200,000 regardless of your filing status, your employer will withhold an additional 0.9% of your wages that are in excess of those amounts for Medicare. Keep in mind: When you file your tax return, the actual Additional Medicare Tax due is computed on the basis of your filing status thresholds ($250,000 married filing jointly; $125,000 married filing separately; $200,000 all others), so you may owe more (or get a credit) depending on your household income and multiple jobs.
If you’re self-employed, you’re responsible for paying additional amounts, bringing the tax bill to 12.4% total for Social Security taxes (on income earned up to the annual limits) and 2.9% for Medicare—plus the extra 0.9% if applicable. If you’re a W-2 employee, your employer pays half of the Social Security and Medicare tax, apart from the 0.9% Medicare surtax.
Your answers on your W-4
Your W-4 is designed to provide your employer with your best guess about what your federal income tax liability will be for the year. It does this by asking for information about your family, income you earn from sources other than your W-2 job, including other W-2 jobs and your spouse’s job, if applicable, and potential deductions and tax credits you might claim that could impact your withholding. Based on how you respond, your employer might withhold more or less of your income.
For example, if you earn income from side jobs, you might include an estimation of how much you expect to make from them. Then, your employer knows to withhold more from your checks each pay period, hopefully helping you avoid a big tax bill later to account for your side hustle earnings. On the other hand, if you note on your W-4 that you plan to claim dependents on your tax return, this might lower the amount your company withholds from your check. Whether you got a tax refund last year or not can be a good indication of how withholding adjustments will impact your take home pay. For those getting a tax refund, adjusting your W-4 withholding could result in more take home pay—at the expense of a smaller refund.
If you anticipate your W-4 might be complicated, consider speaking with a tax professional, as withholding too little can result in fines and penalties. Source