In a bid to spur consumer spending, 17 states are offering sales tax holidays this summer and fall. Consumers shopping during those days can stretch their budgets for back-to-school staples such as clothing, computers and books, and in a few states, bigger purchases of Energy Star products or hunting equipment, too.

Reducing state revenue from sales tax while the economy struggles may seem like a poor budget decision on the states part, but the states are banking on the sales to provide an economic stimulus of sorts, says Richard Ebeling, a professor of economics at Northwood University in Midland, Mich. It s a psychological boost, he says. Local retailers draw in much-needed sales, and consumers get a break on must-have school supplies. States may even see some tax revenue, if the break prompts people to add a few excluded items to their shopping lists.

Of the states that held sales-tax holidays last year, only Georgia has repealed its July holiday, which waived the 4% sales tax on clothing, footwear, school supplies and computers priced at or below various price caps. State legislators cited a $2 billion budget gap and historical losses during the holiday (a claim businesses dispute). Vermont, which offered a back-to-school holiday last year, shifted this year s to March.

Meanwhile, Florida reintroduced its sales tax holiday, which legislators cancelled for the past two years. Illinois and Maryland introduced sales tax holidays for the first time, waiving the tax on clothing and footwear worth up to $100. (Illinois residents can also avoid tax on school supplies worth up to $100.)

But while a sales-tax holiday offers added incentive to hit the mall, be on the alert for fine print. Here's how to take advantage of your state's holiday:

Stick to a budget

A 4% or 6% discount isn t significant enough to warrant impulse purchases or trading up for more expensive jeans or sneakers, says Gail Cunningham, a spokeswoman for the National Foundation for Credit Counseling. Prepare and stick to your shopping list.

Check local participation

Most states leave it to individual towns and counties to decide if they will waive more than the state portion of the sales tax during the holiday. There might still be a county, city or special jurisdiction sales tax in effect, says Carol Kokinis-Graves, a senior analyst with tax advisory firm CCH. Check with the state tax commission to see what your area is doing -- and compare other local rates -- before deciding which area mall to visit. Alabama keeps a list of participating towns.

Mind exemptions

Many states get very specific, so read up on what's included in the holiday, Kokinis-Graves says. Florida, for example, excludes sales made in theme parks or entertainment complexes, while Texas nixes specific items like belt buckles, football pants and personal flotation devices.

Stack sales

Pair the state waiver with store sales and coupons when possible, says J. Craig Shearman, a spokesman for the National Retail Federation, an industry group. Retailers are likely to offer plenty of sales that knock prices to below the states caps. With the economy as tight as it is, what would ordinarily be just a psychological boost becomes a real savings, he says. But not every promotion results in a tax-free purchase. Some states, including Iowa, don t count manufacturer's coupons or rebates when assessing an item s value.

Watch the clock

For a purchase to count, the sale must be processed by the end of the holiday. Online purchases are usually covered. Items that you pre-order or set aside on layaway are unlikely to be, Kokinis-Graves says.

Mark your calendar with these dates for a sales tax holiday near you:

2010 State Sales Tax Holidays

State	Date	State Tax Suspended*	Affected Items**
Alabama	Aug. 6-8	4%	Books worth $30 or less. School and art supplies worth $50 or less. Clothing worth $100 or less. A single purchase of a computer, software and/or computer accessories worth a combined value of $750 or less.
Connecticut	Aug. 15-21	6%	Clothing and footwear worth $300 or less.
Florida	Aug. 13-15	6%	School supplies worth $10 or less. Clothing and books worth $50 or less.
Illinois	Aug. 6-15	6.25%	Clothing, footwear and school supplies worth $100 or less.
Iowa	Aug. 6-7	6%	Clothing worth $100 or less.
Louisiana	Aug. 6-7	4%	For more details, click here
	Sept. 3-5		Firearms, ammunition and hunting supplies of any price.
Maryland	Aug. 8-14	6%	Clothing and footwear worth $100 or less.
Mississippi	July 30-31	7%	Clothing and footwear worth $100 or less.
Missouri	Aug. 6-8	4.225%	School supplies worth $50 or less. Clothing worth $100 or less. Computer software worth $350 or less. Computers and computer accessories worth $3,500 or less.
New Mexico	Aug. 6-8	5%	School supplies worth $15 or less. Clothing worth $100 or less. Computers worth $1,000 or less.
North Carolina	Aug. 6-8	5.75%	Sports and recreational equipment worth $50 or less. Clothing and school supplies worth $100 or less. Computer accessories worth $250 or less. Instructional materials worth $300 or less. Computers worth $3,500 or less.
	Nov. 5-7		Energy Star products of any value.
Oklahoma	Aug. 6-8	4.5%	Clothing and footwear worth $100 or less.
South Carolina	Aug. 6-8	5.75%	For a full list, click here
	Nov. 26-27		Guns, rifles and handguns of any price.
Tennessee	Aug. 6-8	7%	Clothing and school supplies worth $100 or less. Computers worth $1,500 or less.
Texas	Aug. 20-22	6.25%	Clothing, backpacks and school supplies worth $100 or less.
Virginia	Aug. 6-8	4%	School supplies worth $20 or less. Clothing worth $100 or less.
	Oct. 8-11		Energy Star products worth $2,500 or less.
West Virginia	Sept. 1- Nov. 30	6%	Energy Star products worth $5,000 or less.

* State tax only. Local taxes may or may not be waived, depending on location.

** Cost per item, unless otherwise noted.