W-4: How to Fill Out The 2025 Tax Withholding Form

A step-by-step guide to help you fill out a W-4

You’re about to begin that much-needed, new job and your employer hands you an IRS Form W-4 to fill out and submit to them immediately. Don’t wince. This required tax form controls how much tax will be withheld from your paychecks and affects your take-home pay. Form W-4 is your friend and it’s not difficult to fill out.

This doesn’t mean that you’ll owe less taxes at year’s end. You might owe more when you file your tax return depending on the information you’ve included on your W-4. This can happen if your withholding per your W-4 isn’t sufficient to meet your ultimate tax obligation for the year. The form determines whether you’ll pay your taxes paycheck-by-paycheck as the year goes on, in a lump sum at the end of the tax year, and if you’ll owe interest and penalties on an unpaid balance.

Key Takeaways

• IRS Form W-4 dictates how much money is withheld from your gross pay for taxes.
• Step 1 requires you to input personal details while Step 2 is required if you have more than one job or you are married filing jointly with a spouse who works.
• You must list your dependents in Step 3.
• Indicate on the form how much you want withheld from each paycheck in Step 4.
• Sign and date your form so your employer can fill out their portion before it is submitted to the IRS.

Purpose of Form W-4

Form W-4 is called the Employee’s Withholding Certificate. It dictates how much is deducted from your gross income for taxes. Your gross pay is the total amount you’ve earned for the pay period before any taxes or other deductions are withheld. The amount withheld depends on numerous personal factors. Form W-4 walks you through determining what they are so your employer gets the deductions just right.

The total tax withheld from your pay is largely based on your filing status. Your employer is legally obligated to identify you as single or married filing separately if you don’t complete and submit a Form W-4 with your correct information, even if you’re married or qualify as head of household. This can result in more taxes being withheld from your pay. You’ll get the money back in a tax refund at the end of the year but who wants to wait that long?

The 2025 tax year Form W-4 is just one page but it includes five steps that must be completed and three additional pages of helpful guidance and instructions.

Your Personal Details

Step 1 of the Form W-4 is devoted to your personal information. This is where you can declare your filing status. This can be critical if you’re a single parent because you may qualify as head of household. This filing status provides a good many tax breaks and is far superior to filing as a single taxpayer if you qualify. You must have a dependent, be “considered unmarried,” and pay more than half the cost of maintaining your home.

You can check a box at the bottom of the Step 1 section claiming this status or another one. Your employer will base your tax withholding on this information. Step 1 also asks for your name, address, Social Security number, and whether your name matches the name on your Social Security card.

Your Job(s)

Completing Step 2 of the Form W-4 is required if you hold more than one job and/or you’re married and filing jointly with a spouse who also works. Your tax withholding will depend on all your sources of income. Step 2 directs you to use one of three options to finetune how much should be withheld from your pay. Completing Step 3 and a portion of Step 4 depends on the result.

Your first option is perhaps the easiest. You can use the IRS’s online Tax Withholding Estimator. Your second option is to use the Multiple Jobs Worksheet that’s provided on page 3 of the W-4 form along with detailed instructions. There’s a box you can check as your third option indicating that you and your spouse, if applicable, have only two jobs total. The IRS recommends that you use the highest paying job in this case for the best accuracy.

Note

You and your employer can submit your W-4 electronically.

Your Dependents

Step 3 is devoted to your dependents. Keep in mind that they don’t have to be your children. An adult relative can qualify as can an unrelated adult who lives with you all year. Their gross income must be less than $5,050 as of 2025 and you must provide more than half their financial support.

It’s time to do a little math after you determine how many dependents you have. Step 3 of Form W-4 instructs you to multiply each qualifying child who’s younger than age 17 by $2,000 and enter the total. Multiply each adult dependent by $500 and enter the total then add the two totals together.

This information is necessary if you plan to claim tax breaks such as the Child Tax Credit or the Credit for Other Dependents on your return. Your income must be $200,000 or less if you’re single or $400,000 or less if you’re married and filing jointly to qualify as of tax year 2025.

Completing Step 3 of Form W-4 is voluntary. More taxes will be withheld from your pay if you have qualifying dependents and you don’t enter them here. This might help you at tax time if you have other sources of income from which taxes aren’t being withheld. This might be the case if you have investments or you’re a gig worker on the side and you want to make sure you don’t owe a mountain of taxes on that income when you file your tax return.

Step 4 of Form W-4 can help with this type of situation as well.

How Much Do You Want Withheld?

Completing Step 4 of Form W-4 is also optional. This is where you let your employer know that you want more withheld from your paychecks or less. You have three options here as well.

Your first choice is to enter the extra income you want to account for, such as from that gig work or other Form 1099 non-employment income. This section also directs you to a worksheet on page 3 that you can use to reduce your withholding because you expect to claim other deductions rather than just the standard deduction for your filing status. You can also elect to simply cite a simple dollar amount that you’d like withheld for your pay in addition to your regular withholding.

That’s it. You’re done. Just don’t forget to sign and date the form at the bottom. The very last spaces on the form aren’t your concern. Your employer will complete those.

What Changes Have Been Made to Form W-4 Over the Years?

Form W-4 was changed in December 2020 under the terms of the Tax Cuts and Jobs Act (TCJA) that went into effect at the end of 2017. The TCJA eliminated the personal exemptions that taxpayers used to be able to claim for themselves, their spouses, and their dependents.

What If I Want to Make Changes to My W-4?

Simply ask your employer for a new W-4 form to fill out or access the current year’s version online. You can update your W-4 at any time if you want to adjust your withholding or record a change such as getting married, having a child, gaining another dependent, or enjoying a new source of income.

What Happens to the Money That’s Withheld From My Paychecks?

Your employer forwards the money that’s withheld to the IRS on your behalf. The IRS records the receipt and applies it to your tax debt when you file your tax return. The totals are reported on Form W-2 which you’ll receive from your employer after the close of the tax year.

The Bottom Line

Form W-4 is a valuable tool to get your tax withholding just right or as close as possible barring unforeseen circumstances. You can submit a new one to your employer to accommodate any changes if unforeseen circumstances do occur. Preparing the form correctly can prevent you from being hit with a monstrous tax bill when you file your return and it can protect you from having to wait until you receive your tax refund for some much-needed cash if you overpay all year.

The IRS provides straightforward instructions with the form to help you get it right but always check with a tax professional if your tax situation is a little complicated and you’re unsure.