The counties have been helped by stable jobs at several large employers and federal stimulus funding that created thousands of jobs at Savannah River Site, business officials and owners said.
On Friday, Aiken County reported an unemployment rate of 8.3 percent for September -- third-lowest of the state's 46 counties -- and Edgefield County recorded a rate of 9.9 percent for the month, according to data from the state Department of Employment and Workforce.
South Carolina's average unemployment rate was 11 percent in September, down from 11.1 percent the previous month.
"I think relative to other parts of the state the Aiken region did better," said Doug Woodward, a professor of economics at the University of South Carolina's Moore School of Business. "We'll have to see if that is going to continue to be the case as that (stimulus) money winds down during the next year."
The nearly 3,000 short-term jobs created at SRS through the American Recovery & Reinvestment Act have a multiplier effect, creating jobs and sales for companies that do business with SRS and its workers, said David Jameson, the president and CEO of the Aiken Chamber of Commerce.
Fewer workers at SRS will inevitably have an impact on area businesses, said Mike Willis, a co-owner of Tea Garden Gifts in Aiken and chairman of board of directors for Downtown Aiken Development Association.
"People will think about tightening their belts and not spending even more," Willis said. "The good and the bad trickle down. Whenever SRS increases employment, we benefit from that."
In Aiken County, unemployment peaked in January at 10.7 percent and fell to as low as 7.7 percent in May, according to data from the Department of Employment and Workforce.
"I think the stimulus helped Aiken," Woodward said.
Steady work at large county employers such as Kimberly-Clark, Bridgestone/Firestone, Pepperidge Farms and GlaxoSmithKline also has helped keep unemployment from ballooning again, Jameson said.
"They have been stable throughout the slowdown in the economy," he said.
In Edgefield County, employment has been helped by growth at Trenton's call center and distribution center for Urban Outfitters Inc., which sells clothing, accessories, furniture and other items under brands such as Urban Outfitters, Anthropologie and Free People.
The 5-year-old center has about 460 employees and is looking to hire between 150 and 160 seasonal workers for the holiday period, said Jim Bailey, the contact center manager at the site.
Some of those workers might have the chance to transition to full-time positions because of the center's growth, said Bryan Whitney, the contact center director, adding that at the site's current growth rate the company will outgrow its current space by the end of 2011.
"There is a customer-service mentality and also just the natural pleasantness that people possess here," Bailey said. "That comes across in their interactions daily on the telephone."
Many of the call center's workers come from Aiken or Augusta, and many of the distribution workers, who pick and pack orders, come from Edgefield County, Whitney said.
Edgefield County had a much smaller September work force, about 11,200 people, than Aiken County, which had about 76,000 workers.
Edgefield saw a trend similar to Aiken's, with unemployment reaching its peak in January at 12.2 percent and its low in May at 8.5 percent.