Some Iowa employers have already installed the new tax withholding tables that were released Wednesday by the Internal Revenue Service. The new tables enact the Making Work Pay tax credit, a key tax provision included in the American Recovery and Reinvestment Act of 2009 that President Barack Obama signed into law on Feb. 17. The credit equals 6.2 percent of a taxpayer’s earned income, with a maximum credit of $800 for a married couple filing a joint return and $400 for other taxpayers, but is phased out for higher-income taxpayers.

“For most taxpayers, the additional credit will automatically start showing up in their paychecks this spring,” IRS Commissioner Doug Shulman said in a press release. “Since employers and payroll companies will handle this change, people typically won’t need to take any additional action.”

The new withholding tables, along with other instructions related to the new tax law, will be incorporated in new Publication 15-T. This publication will be posted at www.irs.gov this week and will be mailed to more than 9 million employers in mid-March. The IRS asks that employers start using these new tables as soon as possible but not later than April 1.

For employers, installing the new tables into their payroll-processing software should be a relatively simple process, said Jane Buryanek, operations manager at Merit Resources Inc. The Urbandale-based professional employers’ organization handles payroll processing for about 250 companies.

“If they or their payroll administrators are using one of the standard software packages, the new tables should come from the software vendor as a simple download,” she said. “Once those new tables are installed their procedures won’t change, but it is of course important for them to be aware that a change has occurred and to verify that all of their payroll taxes are calculating properly.” Merit has already updated its clients’ software, she said, and most companies will likely receive upgrades from their vendors within the next two weeks.

Though the tax table changes aren’t complicated, other changes that affect health benefits continuations under the Consolidated Omnibus Budget Reconciliation Act (COBRA) and unemployment compensation will “definitely require the employers’ attention,” Buryanek said.