12/29/2009: 2010 Federal Withholding Table Updates Federal withholding tables have changed for wages paid on or after January 1, 2010. Users with active Internet connections may download these updated tables. In CertiflexDimension v9, go to >Help >Software Updates >Check for Updates >Download Updates and >Install Updates. In CertiflexDimension v10, go to >Tools >Software Updates >Check for Updates >Download Updates and >Install Updates. For additional information visit the IRS website at www.irs.gov.