That had been promised by board president Toni Preckwinkle during her campaign last year.
The first roll back happens next year. It will be completely eliminated by January of 2013.
Eliminating the remaining half-penny tax will cost the county about $180 million.
Todd Stroger pushed through a 1 percent increase in the Cook County sales tax. It pushed Chicago's sales tax to the highest in the nation. Friday, the Cook County Board rolled back all of the controversial tax.
When campaigning for Cook County Board president, Toni Preckwinkle promised to rid the county of the sales tax increase imposed by the previous administration.
"The increase in the sales tax has been problematic for working families and especially difficult for businesses," Preckwinkle said.
The sales tax was one penny on every dollar. Some businesses complained that the tax hike pushed customers to other counties to make purchases.
Last year half of the tax was rolled back. And Friday a majority of Cook County Board commissioners voted in favor of rolling back what's left of the tax hike.
"It brings 'em back to where they need to be, in Cook County, as opposed to going over state and county lines," said Cook County Commissioner Liz Gorman, 17th District.
"I think it's important symbolically and it's important for the whole economy that the president honored her commitment to reduce this, that we get this out of the way, that we can now work on our budget moving forward," said Cook County Commissioner Larry Suffredin, 13th District.
Half of the tax hike was cut out July 1 last year. With Friday's vote, one-fourth of the 1 percent tax would end January 1, 2012
The final fourth would stop January 1, 2013, rolling back the tax hike completely in two years.
Some commissioners who voted against the rollback wonder if the move was hasty as the board works on the county's budget.
"We still have the same purse we had 16 years old," said Cook Commissioner Deborah Sims, 5th District. "Where everything else the economy has grown and we haven't, and we have nothing else to grow that economy with."
"We can't afford to have more people laid off, and this crew that came in they really didn't look at the overall impact of what it is that she wants to do," said Cook County Commissioner Earlean Collins, 1st District.
Commissioners were still working on the budget Friday evening. President Preckwinkle hopes to have her first budget proposal approved some time Friday night.