A problem that has kept Fulton County from setting its millage rate will mean residents' tax bills are delayed for at least a month and revenue collections will likewise be delayed.

If the county, cities or school districts borrow money to cover the gap between when taxes were expected and taxes arrive, it means that some of the taxes that residents pay will go toward paying interest and administrative fees for the borrowing, as opposed to paying for programs. The county may also consider delaying some programs, if the problem persists, Fulton County Chief Financial Officer Sharon Whitmore said.

The bills usually go out in July or August, and are due October 15. But a problem in calculating the tax digest means tax bills will not be sent before mid-September, and payment would not be due until November, at the earliest.

The delay increases the likelihood that Fulton County, its cities and the schools will have to borrow money to meet their obligations. A spokeswoman for Fulton County schools, Susan Hale, said in an email that the district is “watching our cash situation closely” and will have to borrow “if the delay continues for an extended time.”

“(Tax bills) will not go out according to the normal time frame this year,” Whitmore said. “It’s a big deal. We need to resolve it.”

Fulton County has not yet set its tax rate because the system that calculates the tax digest had trouble differentiating between increases due to reassessed property and those that come from new growth.

Georgia law requires governments to decrease the millage rate as values rise, or to advertise that they are increasing taxes if values rise and the millage rate stays the same. Without knowing what the actual values are, Fulton has been able to do neither.

David Fitzgibbon, Fulton’s chief appraiser, said in an email that there had been indications last summer that there might have been an error in the calculation. Attempts to fix the problem this summer only uncovered more issues with the calculations.

At a Fulton County commission meeting Wednesday, Vice Chairman Liz Hausmann said everything the county does is predicated on collecting taxes. To say that there will be a delay in doing so is a problem, she said, is a “major understatement.”

“This is no way to do business,” she said. “I don’t know at what point we declare that an emergency, but I think we’re kind of close.”