BlogTax EstimatorTax Withholding Calculator: Get Your W-4 Right
Tax Planning5 min readJune 22, 2025

Tax Withholding Calculator: Get Your W-4 Right

Too much withholding and you're giving the IRS a free loan. Too little and you owe in April. Here's how to dial it in.

Share

Instant Answer

Your W-4 tells your employer how much federal income tax to withhold from each paycheck. The goal is to withhold as close to your actual liability as possible. The IRS Withholding Estimator (irs.gov/W4app) is the most accurate free tool for W-2 employees.

The True Cost of Getting Withholding Wrong

The average federal tax refund in 2023 was $2,753. Most people see this as a bonus — but it's the opposite: you overpaid by about $230 per month throughout the year.

The IRS issued $334 billion in refunds in 2023, averaging $2,753 per return. Source: IRS Filing Season Statistics (2023) — Source

That money could have been earning interest, reducing high-rate debt, or sitting in your emergency fund. Instead, it was an interest-free loan to the federal government.

How the W-4 Works

Your W-4 tells your employer's payroll system how much federal income tax to withhold. The 2020 redesign replaced the old "allowances" with:

Step 1: Filing status Step 2: Multiple jobs or spouse who works Step 3: Dependent credits Step 4: Other income, deductions, additional withholding

About 50% of workers have not updated their W-4 since the 2020 redesign, leaving many with inaccurate withholding. Source: American Payroll Association (2022) — Source

When to Update Your W-4

  • New job or significant raise
  • Marriage or divorce
  • Having a child
  • Buying a home
  • Taking on significant freelance income
  • Major capital gains

For side income: request additional flat-dollar withholding per paycheck in Step 4(c) instead of making quarterly payments.

About 30 million taxpayers underwithhold each year. Source: GAO Report GAO-19-628 (2019) — Source

See also: paycheck tax calculator, IRS tax estimator, and the tax estimator guide.

Get Started with Avenue to track your withholding against your projected liability.

A

Financial Editor

Insights on AI-native personal finance, financial independence, and building a money system that runs itself.

Frequently Asked Questions

How do I know if my withholding is correct?
Run the IRS Withholding Estimator mid-year with your year-to-date income and withholding. If you're on track to over- or under-withhold by more than a few hundred dollars, submit a new W-4.
What changed about the W-4 form?
The IRS redesigned the W-4 in 2020, eliminating the old "allowances" system. The new form asks for income from multiple jobs, dependents, other income, and deductions.
Can I change my W-4 at any time?
Yes. You can submit a new W-4 to your employer at any time. The new withholding takes effect within a pay period or two.

Ready to run your finances on autopilot?

Avenue connects all your accounts and gives you an AI-powered view of your full financial picture — in minutes.

Get Started