A $100 stack of shirts actually would cost $100, instead of $108, during the first weekend of December if lawmakers stick with a Senate plan to offer a sales tax break about three weeks before Christmas.

The Senate voted earlier this week to create a tax-free weekend each December similar to the one that sends shoppers racing to the malls before school starts in August. The House has not voted on the measure, so it will be up to a House-Senate conference committee to decide whether to make it part of a final version of House Bill 3, which raises sales and business taxes to pay for cuts in school property taxes.

The new tax-free weekend would begin on the first Friday in December and last through Sunday. Shoppers would not pay sales tax on most clothing items that cost less than $100 apiece. The Senate proposal also extends the tax break to backpacks and some school supplies.

The sales tax rate in Austin is 8.25 cents per dollar. The House has voted to raise sales taxes by 1 cent across the state, and the Senate voted for a half-cent increase, another difference that will be ironed out in a conference committee.

Sen. Eliot Shapleigh, D-El Paso, said he proposed the December break because the sales tax is a regressive tax, meaning low-income families pay a higher share of their income to cover the tax on such basic items as clothes and food. Pointing to studies from the nonpartisan Legislative Budget Board, he said plans passed by the House and Senate will shift more of the Texas tax burden to poor families.

"Somehow, we must lessen the impact of these regressive taxes on low- and middle-income Texans," Shapleigh said.

Comptroller Carole Keeton Strayhorn said she expects the December holiday would save Texans $126 million over two years in sales taxes on the items that are exempt. That's money that otherwise would go to state and local governments, but she said those bodies will bring in more money during those periods than they would if sales tax were collected.

"We get that economic shot in the arm because while people are out, they buy other things," she said, referring to items that remained taxable. Also, she said, the holiday draws shoppers from out of state who spend money at hotels and restaurants.

Local governments, which charge up to 2 cents in sales tax, can decide to charge that tax during the holiday, but Strayhorn said that almost never happens.

Lorie Kennedy, marketing manager at the Prime Outlets in San Marcos, said the August sales tax holiday rivals the weekend after Thanksgiving as the busiest weekend of the year for her mall.

GOP Rep. Jim Keffer of Eastland, chairman of the tax-writing House Ways and Means Committee, said he couldn't predict whether the proposal will survive the conference committee. He said the key goals for House negotiators will be making sure that the bill is revenue-neutral, meaning it does not raise or cut taxes overall, and that property tax cuts are as large as possible.

"Everything's going to be looked at and scrutinized," he said.