How to Fill Out a W-4 at Your New Job

The Money Class You Never Got in School

How to Fill Out a W-4 at Your New Job (Without Screwing It Up)

New job, new vibes—until HR slides you a W-4 form and you're staring at it like it's written in Elvish. You're not alone. Most people just wing it, then act shocked when their paycheck is short or they owe hundreds in April. Let’s fix that.

Wait—W-4 or W-2?

Quick heads up: the W-4 is the form you fill out when you start a job. The W-2 is what your employer sends you after the year ends to tell the IRS how much you made. This post is about the W-4—the one that determines how much federal income tax comes out of each check.

Why the W-4 Even Matters

The W-4 doesn’t change how much you make—it changes how much you see. Too much withheld? Your check is smaller than it needs to be. Too little? You’ll owe the IRS later and hate your life in April.

Step-by-Step: How to Fill This Thing Out

Step 1: Your Info

Name, address, Social Security number, and filing status. If you're single with no kids, you’re probably marking "Single" or "Single or Married filing separately." If you support someone else or have dependents, “Head of Household” might apply, but only if you meet the IRS’s exact rules (don’t play around here).

Step 2: Got more than one job?

If you’re working two jobs or your partner also brings in a paycheck, this part matters. You can either:

• Use the IRS tax estimator to do the math (honestly not as bad as it sounds)
• Check the box if your jobs pay about the same
• Or leave it blank and risk owing later

If you freelance, deliver for DoorDash, or do anything self-employed on the side, this is also where you account for that—unless you like tax bills that hit like a Netflix subscription cancellation.

Step 3: Dependents

If you have kids or support someone financially and you make under $200K, you might be able to reduce your tax withholding here. But again, don’t guess. This step doesn’t apply to most people in their 20s unless you're a parent or caregiver.

Step 4: Extra Stuff

This is the "adjustments" zone. You can enter:

• Extra income (like freelance work)
• Deductions (like student loan interest or education credits)
• Or a flat dollar amount you want taken out each pay period

If you’re not sure, leave it blank for now and revisit once you’ve run your numbers.

Step 5: Sign it

No signature = no paycheck. Sign, date, and turn it in. You can update it any time—yes, even halfway through the year if you realize you messed something up.

How to Avoid Getting Wrecked at Tax Time

If you’ve ever gotten a fat refund check, that just means you were overpaying the whole year. The IRS was holding your money for free. On the flip side, if you owed hundreds or thousands, you probably under-withheld. The goal? Get as close to zero as possible—without giving the IRS a free loan or owing them one.

So… Should You Withhold More or Less?

If you’re someone who struggles to save and likes the refund dopamine hit, keep more withheld. If you’re disciplined, want more cash now, and are investing or saving that difference, withhold less.

Use ChatGPT or the IRS Estimator

"I'm 24, single, starting a new job making $52,000 a year. I want my paychecks to be as accurate as possible and avoid owing taxes later. How should I fill out my W-4?"

Or go straight to the IRS Withholding Estimator to get exact recommendations.

Scenarios That Actually Matter

You freelance or side hustle: You're technically self-employed. The IRS still wants that tax money. You can either pay estimated taxes quarterly or adjust your W-4 at your main job to account for it. Option B is less stressful.

You live at home and claim “exempt”: Only claim exempt if you made less than the standard deduction last year ($13,850 in 2025) and you expect the same this year. Don’t fake this or the IRS will come knocking with penalties.

You got married or divorced mid-year: Update your W-4 immediately. Filing status changes everything about how your taxes work.

Big Mistakes People Make

• Leaving the form blank and letting the system guess for them (don’t do this)
• Checking “exempt” when it’s not actually true
• Ignoring multiple job income (and then panicking at tax season)

Bottom Line

The W-4 is one form that controls every paycheck you get from that employer. If you want to know why your paycheck is smaller than expected—or why you owed money last April—it probably started here.

You don’t need to be a CPA. You just need to be smarter than the default settings. Take 10 minutes, think about your money goals, and adjust accordingly.

You’re in MoneyMode now. Don’t just sign stuff—understand what it does to your bag.