Employers in the U.S. are starting to warn their workers to prepare for slimmer paychecks if Congress fails to vote on an extension of Bush-era tax cuts.

“I’ve been doing payroll for probably close to 30 years now, and never have we seen something like this where it gets that down to the wire,” said Dennis Danilewicz, who manages payroll services for about 14,000 employees at New York University’s Langone Medical Center. “That’s what’s got a lot of people nervous. All we can do is start preparing communications with a couple of different scenarios.”

Lawmakers won’t start debating whether to extend the cuts, which expire Dec. 31, until after the Nov. 2 elections. Because it takes weeks to prepare withholding schedules, the Internal Revenue Service will probably have to assume the cuts will expire and direct employers to increase payroll deductions starting Jan. 1, experts say.

“We’re kind of stuck between a rock and a hard place,” said Ron Moser, head of human resources for the school district of Kenmore-Town of Tonawanda, New York, which pays about 1,900 teachers, custodians and aides each month. In upstate New York, where winter heating costs are among the highest in the country, many school employees earn between $20,000 and $40,000 a year, he said, and losing $50 in a paycheck is “a significant dollar amount.”

Employees Calls

“We’re starting to get the calls” from employees asking what they need to do for the next tax year, Moser said.

President Barack Obama and most Democrats want tax cuts extended for middle-income earners and to end for the wealthiest Americans, the top 2 or 3 percent of earners. Republicans want tax cuts extended for everyone, arguing that an increase makes little sense as the economy recovers from the worst recession since the 1930s. Tax cuts went into effect in 2001 and 2003.

For Moser, the challenge of the moment is keeping people in the Buffalo suburb, home to about 78,000 residents, calm about what will happen in January. The area has several manufacturing employers -- including 3M Co., General Motors Co. and Praxair Inc. -- and unemployment is 7.6 percent, lower than the national rate of 9.6 percent. Still, many people are worried, he said.

“The bulk of our employees don’t understand” the coming tax debate in Congress, Moser said. “When they see this type of thing happening they go into panic mode. They don’t follow what’s going on.”

June 2001 Rates

If Congress fails to act, income tax rates will revert to higher levels dating from June 2001.

For a married couple with an income of $80,000, that would drain an extra $221.48 in withholding from a semi-monthly paycheck, according to calculations by the Tax Institute at H&R Block. Married individuals earning $240,000 a year would lose an additional $557.78 to withholding in a single semi-monthly paycheck. The Tax Institute at H&R Block calculated federal tax rates for single-income earners and married taxpayers without children.

Paychecks could shrink in January and into February, depending on how long it takes Congress to act.

January could well be a time of “sticker shock” for salaried employees and their employers, said Kathy Pickering, executive director of the Tax Institute, an independent research division at Kansas City, Missouri-based H&R Block Inc.

“If the laws get passed late in December, it’s just necessarily going to take one to three weeks to get those payroll tables updated and implemented into the system,” Pickering said.

Blow to Spending

Allowing the tax cuts to expire, even temporarily, would deal a blow to disposable income and could curtail the consumer spending that accounts for about 70 percent of the economy, said Alec Phillips, a Washington-based economist at Goldman Sachs Group Inc.

“The longer the expiration lasts, the more significant the impact will be,” he said.

Economists raised estimates for consumer spending in the third quarter to 2 percent from 1.9 percent, according to the median forecast on a Bloomberg News survey this month. Spending rose at a 2.2 percent pace in the second quarter. The Commerce Department will release third-quarter data on Oct. 29.

Making a withholding-rate change could take longer for small businesses that don’t outsource payroll services, experts said. If a business can’t react fast enough, employees could recoup any over-withholding by filing a new W-4 tax form to temporarily lower their federal withholding rate.

Another option is to wait until 2012 when workers file their tax returns for the previous year.

Taxpayer Strategy

Taxpayers could use the same strategies if Congress reinstates the tax cuts next year and they need to recoup the extra withholding.

Jodi Parsons, manager of payroll and accounts payable at IFMC, a health care management company based in West Des Moines, Iowa, said if the IRS issues two sets of withholding tables, her two-person office could be overwhelmed with processing changes to W-4 forms.

“We’d have to basically go back and hand calculate checks for all 800-900 employees to determine whether or not we need to deduct additional taxes from them or refund taxes,” Parsons said. “We’d like to see changes in mid-November just to make sure we have time.”

There are now six federal tax brackets, ranging from 10 percent to 35 percent. If Congress doesn’t act, there will be five rates with the top bracket reaching 39.6 percent.

Nov. 20 notice

Last year, the IRS alerted payroll departments on Nov. 20 about the 2010 tax tables, said Scott Mezistrano, senior manager of government relations at the American Payroll Association in Washington. He said a delay in guidance from the IRS could increase costs for some small businesses.

The Treasury Department last week issued a statement that it was “maintaining flexibility” with regards to the release of the withholding tables for 2011.

If the IRS issues tables in mid-November and then again later, businesses will double their programming costs, Mezistrano said. A related concern, he said, is if Congress makes a last-minute decision to extend the cuts and companies aren’t able to implement the change before January.

Business owners may face “tons of angry employees pounding at my office door saying, ‘What have you done to my paycheck?’” Mezistrano said.