The Hartford Courant is reporting that over 700 Connecticut employees contacted the state to ask why their December 2011 tax withholding was incorrect. Apparently this widespread issue is due to the state attempting to apply some retroactive tax adjustments to worker’s pay. The reason so many are experiencing issues in December is automated payroll systems miscalculate income tax owed when workers have either overtime pay, a Christmas bonus or a buyback of unused sick days.

Provided your pay is regular each period the Connecticut withholding tax tables appear to work just fine. When payroll is different weekt to week (as may be the case with vacation or holiday pay or year end bonus) then the CT Withholding tables (provided by the state) may inaccurately withhold too much.

According to the Courant:

Because the increase in state income taxes began in August, but was retroactive to the beginning of the year, state income tax withholding is designed to both take out the right amount for the current pay period and for the first two-thirds of the year. But when employees have higher pay than usual, many payroll systems assume they’ve been earning that amount all year.

Even the state of Connecticut had overwithholding issues, with Department of Transportation workers after Tropical Storm Irene. The state did not make a fix to its software, because the same thing happened again in December, for corrections officers who received holiday pay and overtime.

“Those employees have been refunded where possible,” said Tara Downes, spokeswoman for the state Comptroller.

The good news: no worker, no matter how plumped up his check is with overtime or bonuses, will see this glitch starting Sunday. That’s because the systems will no longer be trying to calculate retroactive withholding.

via: Hartford Courant  and State of CT Withholding Tables for 2012 (PDF)