Two jobs withholding explained
How working multiple jobs affects your tax withholding and what you need to know to avoid underpayment penalties.
- •Each employer withholds as if their job is your only income
- •This can result in under-withholding when you have multiple jobs
- •You may owe taxes (and penalties) when you file your return
- •Use the IRS Tax Withholding Estimator to calculate the right withholding
Updated Jan 2026
The problem with multiple jobs
If you work multiple jobs, you've probably noticed something: each employer withholds taxes as if that job is your only source of income. This can lead to significant under-withholding, which means you might owe taxes (and potentially penalties) when you file your return.
For example, you work two part-time jobs, each paying $40,000 annually. Each employer withholds as if you only make $40,000, applying the standard deduction and lower tax brackets. But your total income is $80,000, which is taxed at higher rates. You'll likely owe taxes when you file.
This happens because the withholding system doesn't know about your other income sources. Each employer calculates withholding independently, assuming their job is your only income.
Key takeaways:
- Each employer withholds as if their job is your only income
- This can result in under-withholding when you have multiple jobs
- You may owe taxes (and penalties) when you file your return
How to fix it: adjusting your W-4
The IRS provides tools to help you calculate the right amount of withholding when you have multiple jobs:
Important
If you under-withhold by too much, you may face penalties. The IRS requires you to pay at least 90% of your current year's tax liability or 100% of last year's liability (110% if your AGI is over $150,000).
Option 1: Use the IRS Tax Withholding Estimator
The IRS Tax Withholding Estimator is the most accurate tool. It accounts for multiple jobs and their combined income, your filing status and dependents, deductions and credits, and other income sources.
The estimator will tell you exactly how to fill out your W-4 forms to achieve the right amount of withholding.
Option 2: Use the W-4 Multiple Jobs Worksheet
The W-4 form includes a 'Multiple Jobs' section with a worksheet. Fill out your primary job's W-4 normally, then use the worksheet to calculate additional withholding for your secondary job(s).
Option 3: Request additional withholding
You can request additional withholding on one of your W-4 forms. This is a simple approach but requires you to estimate the right amount.
Key takeaways:
- Use the IRS Tax Withholding Estimator for the most accurate calculation
- The W-4 Multiple Jobs worksheet is another option
- You can request additional withholding on one W-4 form
What happens if you don't adjust
If you don't adjust your withholding for multiple jobs, you'll likely owe taxes when you file your return. Depending on how much you under-withhold, you may also face penalties.
Underpayment penalty: If you owe more than $1,000 when you file and haven't paid at least 90% of your current year's tax liability (or 100% of last year's), you may face an underpayment penalty.
For example, you work two jobs and under-withhold by $3,000. When you file, you owe $3,000 plus potential penalties and interest. This could have been avoided by adjusting your W-4 forms.
The penalty is calculated based on how much you under-withheld and how long you under-withheld. It's typically a percentage of the underpayment amount.
Key takeaways:
- Under-withholding can result in owing taxes when you file
- You may face penalties if you under-withhold by too much
- The penalty is based on the amount and duration of under-withholding
Want to see this with your numbers? Try the calculator with your numbers →
What to do next
Next steps to address this paycheck question or situation.
If you work multiple jobs, take these steps to avoid under-withholding:
- Use the IRS Tax Withholding Estimator: Enter information about all your jobs, income sources, and deductions. The estimator will tell you exactly how to fill out your W-4 forms.
- Fill out your primary job's W-4 normally: Use your actual filing status, dependents, and other information.
- Adjust your secondary job's W-4: Use the estimator's recommendations or the Multiple Jobs worksheet to calculate additional withholding.
- Update when your situation changes: If you start or stop a job, get a raise, or have other income changes, update your W-4 forms accordingly.
- Check mid-year: Use the estimator again mid-year to make sure you're on track, especially if your income or job situation has changed.
Pro Tip
The IRS Tax Withholding Estimator is updated annually and accounts for current tax law. It's the most accurate way to ensure you're withholding the right amount across multiple jobs.