Amazon Goes to Great Lengths to Avoid Sales Taxes Inc., the world's largest online retailer, hasn't charged sales tax in most states since its founding in 1994. And it has taken some extreme measures to keep it that way. A close examination of Amazon's corporate practices, based on interviews with more than a dozen former employees and people who have done business with the Seattle company, as well as a review of corporate documents, indicates that the company believes its sales-tax policy is critical to its performance.