The Internal Revenue Service released updated income-tax withholding tables for employers to implement in 2013.

In addition, employers should also begin withholding Social Security tax at the rate of 6.2 percent of wages paid following the expiration of the temporary two-percentage-point payroll tax cut in effect for 2011 and 2012. 

Employers should start using the revised withholding tables and correct the amount of Social Security tax withheld as soon as possible, but not later than February 15, 2013. For any Social Security tax underwithheld before that date, employers should make the appropriate adjustment in workers’ pay as soon as possible, but not later than March 31, 2013. 

Employers and payroll companies will handle the withholding changes, so workers typically will not need to take any additional action, such as filing out a new W-4 withholding form. As always, however, the IRS urges workers to review their withholding every year and consider submitting revised W-4 forms as needed.