The Society for Human Resource Management (SHRM) provided this update on January 8, 2013:
The IRS released the updated income tax withholding tables on Jan. 3, 2013 reflecting the new changes to the tax code approved by Congress on New Year’s Day. The updated tax guidance includes detailed tables on the new income-tax withholding rates and other information that employers need to update their payroll systems to comply with the new withholding rates.
In addition, employers must begin withholding Social Security payroll tax at the rate of 6.2 percent of wages earned. The temporary two-percentage-point payroll tax cut in effect for the past two years was not extended and expired on Dec. 31, 2012.
The article from SHRM also suggests that if employees want to make changes to their tax withholding they must submit a 2013 W-4 tax withholding form.
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