The IRS has not released the 2018 Form W-4, Employee’s Withholding Allowance Certificate which was originally scheduled for February 15. Therefore, employees are to continue using the 2017 Form W-4 until February 28, 2018 when the new form should be released. At this time employees will have 30 days to submit updated form W-4.
The IRS has released the 2018 Publication 15, Employer’s Tax guide which is available on their website. Note the withholding guide indicates employers may use 22% as the supplemental rate from 2018 – 2025. In addition, the requirement for employees to submit updated Form W-4 within 10 days of changes has been suspended until further notice.