Sign up for Chalkbeat Chicago’s free daily newsletter to keep up with the latest news on Chicago Public Schools.Hold off on back-to-school shopping just a little longer — your wallet will thank you.Families across Illinois can save a bit of money when they go shopping this week because of the state’s upcoming sales tax holiday. Starting Friday, the state’s 6.25% sales tax will be cut to 1.25% on qualifying school supplies and clothing for children and teens. If a store has a higher sales tax than the standard, it will decrease the rate by 5 percentage points. Not all parents and educators will get that relief this back-to-school season. Illinois is one of just 17 states implementing a sales tax reduction before students return to school this year, according to the Federation of Tax Administrators. The tax holiday comes as school supplies have grown more expensive, adding to the rising costs frustrating many Americans. Since last year, the prices of items such as lunch boxes, notebooks, and index cards have increased by more than 20%, according to The Century Foundation, a progressive policy think tank. Here’s what you need to know before going back-to-school shopping.When is the tax holiday?This year’s back-to-school sales tax holiday in Illinois runs from Aug. 7 through Aug. 16. In Chicago, that means families and educators can shop until about a week before K-12 students kick off the new school year on Aug. 24. What items are eligible for a reduced sales tax?Many school supplies are included in this year’s sales tax reduction. Shoppers can purchase eligible items at brick-and-mortar stores and most online stores. Some examples are: BindersBackpacksCalculatorsNotebooksCrayons, colored pencils, markers, regular pencils, pens, and erasersLunch boxesFoldersGlue and tapeRulersLoose-leaf paperThe 10-day period includes sales tax reductions for certain clothing items, too. Each item must be under $125 to qualify. Eligible clothing includes everyday essentials and other items such as raincoats, lab coats, mittens, scarves, belts, and school uniforms.The reduced sales tax also applies to most shoes and socks that cost less than $125. What isn’t eligible? There are a few categories of items that do not qualify for a reduced tax rate, including sports gear, protective equipment, art supplies such as clay and paints, textbooks, computer supplies, and electronics. The following items also do not qualify for the tax holiday:CosmeticsHair accessoriesNonprescription sunglassesJewelry and watchesUmbrellasCan I use coupons or exchange an item?When determining whether a clothing or footwear item is under $125, shoppers should use the price listed by the store, including markdowns. However, applying a coupon that lowers an item’s price below $125 does not qualify it for the sales tax reduction.If an item purchased during the tax holiday needs to be exchanged for a different size or color after the tax holiday ends, no extra sales tax is applied. Makiya Seminera is a reporter covering how the state and federal government affect education in Chicago and across Illinois. Contact Makiya at mseminera@chalkbeat.org.