The IRS released Notice 1036 on January 11th, updating the income tax withholding tables for 2018 to reflect changes made by the recent tax law passage.
In the recent news release, the IRS states:
Employers should begin using the 2018 withholding tables as soon as possible, but not later than Feb. 15, 2018. They should continue to use the 2017 withholding tables until implementing the 2018 withholding tables.
The new withholding tables are designed to work with the Forms W-4 that workers have already filed with their employers to claim withholding allowances. This will minimize burden on taxpayers and employers. Employees do not have to do anything at this time.
The new tables reflect the increase in the standard deduction, repeal of personal exemptions and changes in tax rates and brackets.
To help people determine their withholding, the IRS is revising the withholding tax calculator on IRS.gov. The IRS anticipates this calculator should be available by the end of February. Taxpayers are encouraged to use the calculator to adjust their withholding once it is released.
The IRS is also working on revising the Form W-4. The calculator and new Form W-4 can be used by employees who wish to update their withholding in response to the new law or changes in their personal circumstances in 2018, and by workers starting a new job. Until a new Form W-4 is issued, employees and employers should continue to use the 2017 Form W-4.