Three more states have joined the growing list where youll be charged sales tax on Amazon purchases: Indiana, Nevada, and Tennessee. Amazon already collected tax in 16 states, and in 2016, South Carolina will join them, bringing the number up to an even 20. Technically speaking, youre supposed to add up purchases on your tax returns (the use tax) no matter where you are, but that oft-ignored rule has increasingly given way to automatic point-of-sale charges. This hasnt happened without strong pushback from Amazon and other online retailers, though;