Idaho State Tax Commission

Save Yourself from a Tax Bill: Update Your W-4 Now!

Make sure you have the right amount of income taxes withheld from your paycheck. Update your W-4 at least once a year or to account for changes in your life.

Quick links!

Retired? Scroll down for info on retirement and other sources of nonwage income.

Steps to take NOW:
  1. Use the withholding estimator at to estimate your federal withholding. Update the federal Form W-4 with that information.
  2. Use page 2 of the Form ID W-4 to estimate your Idaho withholding. Fill out Form ID W-4 with that information.
  3. Give both W-4 forms to your employer.
If you owe money with your state tax return:
  • If you pay your income taxes by the April due date, you won't be charged penalty and interest. You can make prepayments using our free QuickPay service.
  • If you can't pay your taxes by the due date, penalty and interest apply. You can request a payment plan to spread out your payments.

Guidance for retirement and other sources of nonwage income

If you're receiving retirement or other sources of nonwage income:

  1. Determine if the income is taxable in Idaho.
    • See the Idaho Income Tax Instructions for guidance
    • Taxable income can be:
      • Retirement income
      • Interest
      • Dividends
    • Generally, Idaho doesn't tax Social Security income.
  2. If the income is taxable, follow the next steps.

Note: The entity paying the nonwage income might not withhold Idaho tax. It's your responsibility to estimate the tax you'll owe and be prepared to pay it.

If the entity paying the nonwage income will withhold Idaho tax for you:

  1. Use the Form ID W-4 to determine:
    • Your Idaho withholding status
    • Your number of Idaho allowances
    • Any additional amount to withhold
      • See Form ID W-4 instructions
      • Consider each source of taxable income as a "job"
  2. Use the information to complete a W-4, or use the entity's W-4 substitute

If the entity paying the nonwage income won't withhold Idaho tax for you:

  1. Estimate your income tax for the nonwage income source:
    1. Estimate your annual income for the source
    2. Estimate your tax on the income. Use the 2019 income tax rate schedule to estimate the total tax you'll owe.
  2. Pay the tax you owe.
    • Make estimated payments directly to the Tax Commission
      • Use Form 51, Estimated Payment of Idaho Individual Income Tax, or
      • Use Quick Pay, online (no log-in needed).
    • Pay the tax on or before April 15

Page last updated January 20, 2021. Last full review of page: December 20, 2018.

This information is for general guidance only. Tax laws are complex and change regularly. We can't cover every circumstance in our guides. This guidance may not apply to your situation. Please contact us with any questions. We work to provide current and accurate information. But some information could have technical inaccuracies or typographical errors. If there's a conflict between current tax law and this information, current tax law will govern.