As parents, teachers and students get ready for school to begin, many states will enact sales tax holidays designed to help soften the financial blow of back to school purchases.During the holiday, which often lasts an entire weekend, sales taxes are not collected, thereby providing a small discount for shoppers and – in theory at least – a sales boost for retailers.As of July 25, 2016, 17 states had sales tax holidays scheduled. Some states have multiple holidays including not only school supplies but energy saving products, hunting equipment and hurricane preparedness items.Related: HERE’S WHAT AMAZON IS TEACHING MALLSControversyAs with anything involving taxes, there is plenty of disagreement about whether a sales tax holiday does any good or not. According to the National Retail Federation, back-to-school and college spending will reach $75.8 billion this year. How much of that will be due to sales tax holidays is unknown.Proponents say any lost tax revenue is more than made up for by increased spending which provides an economic boost to states with a sales tax holiday. Opponents say all the holiday does is shift the time frame for spending and that no significant revenue increase happens.The need to hire additional workers to handle the Black Friday-like crowds some stores experience is another cost factor. Of course, on the plus side, those workers earn additional income which they likely spend in the same state where they earned it.Retail WinnersDespite often having to bring in extra workers and the need to reset registers to account for items that are nontaxable during the period, most retailers believe the extra traffic and sales more than make up the difference.That said, the real retail sales tax holiday winners are mostly those who sell items that are excluded from taxes during the holiday. Even for just the back-to-school sales tax holidays, the winners list can be varied.Related: DEPARTMENT STORES ARE IN REAL TROUBLESome Familiar NamesAmong retailers that stand to gain the most in sales are those who sell clothing, shoes, computers, electronics and school supplies.Some familiar names dot that list including: Costco Wholesale Corp. (NASDAQ:COSTC), Wal-Mart Stores Inc. (NYSE:WMTC), Target Corp. (NYSE:TGTC), Dillard’s Inc. (NYSE:DDSC), Macy’s Inc. (NYSE:MC) and Kohl’s Corp. (NYSE:KSSC) in department and specialty retail.In addition to those stores, school supplies and electronics are also sold by Office Depot Inc. (NYSE:ODPD) and Staples Inc. (NASDAQ:SPLSD). Computers and related products by Apple Inc. (NASDAQ:AAPLC), Intel Corp. (NASDAQ:INTCA) and Microsoft Corp. (NASDAQ:MSFTC) should also do well.Finally, one retailer most people don’t think about, Amazon.com Inc. (NASDAQ:AMZNC) will sell all of the above and more – including lots and lots of books since e-commerce retailers are also excluded from collecting sales tax during sales tax holidays.