Amazon has been paying sales tax in the 45 states that charge it, but that hasn't been the case for many other online retailers, or even some of the sellers in Amazon's marketplace. That's about to change. The Supreme Court ruled June 21 that states can impose sales taxes on out-of-state retailers, including those that don't have a physical presence in the state. Judging by the state sales tax rates compiled by the Tax Foundation and the estimated revenues from new ecommerce taxation put forth by the Government Accountability Office, states would be able to collect $8 billion to $13 billion more in sales tax than in 2017. Half would come from marketplace sellers on Amazon, eBay, Etsy, and similar sites. Based on information from the Tax Foundation and the GAO, here is the impact of that court decision once all states enact ecommerce tax laws of their own.