Idaho State Tax Commission

Idaho State Tax Commission

Tax Commission News Release

Avoid a tax surprise; adjust your paycheck withholding now

BOISE, IDAHO — July 26, 2018 — Recent tax laws have changed the amount of income taxes withheld from employee paychecks. If you don't withhold enough tax, you could have an unexpected tax bill when you file your 2018 income tax return.

The Idaho State Tax Commission is urging you to review your federal Form W-4 now to see if you have the right amount of federal and state income taxes withheld from your paycheck.

Steps to take:

  1. Use the withholding calculator at to estimate your federal withholding.
  2. Use the 2018 W-4 Worksheet for Idaho at to estimate your Idaho withholding.
  3. Make any needed changes to Form W-4 and give it to your employer.

Use the Form W-4 to update both your state and federal withholding. Idaho doesn’t have a separate W-4 form. If you’ve already updated your federal withholding, you should also update the withholding for Idaho. Using the federal allowance number for Idaho could cause miscalculations for your Idaho withholding. 

“All Idaho employees should take the time to review and update their W-4s. We want them to act now to avoid a surprise when they file their taxes next year,” said Renee Eymann, Public Information Officer with the Tax Commission. 

Law changes that affect 2018 tax returns

New federal and Idaho tax laws lowered the income tax rates, increased the standard deduction, eliminated the personal and dependent exemptions, and capped or eliminated most itemized deductions. Idaho also created a new Child Tax Credit. All these changes have significantly affected your federal and Idaho withholding.  

For more information about withholding, visit the W-4 page at The page includes resources including:

  • A video on filling out the 2018 W-4 Worksheet for Idaho
  • Guidance for retirement and other nonwage income
  • Examples on how the law changes affect withholding for a typical family and a single person  


Posted 07-26-2018
tax pros news release general

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.