Retailers have been busy over the weekend with Presidents Day promotions and sales, but Amazon had a significant surprise discount of its own. From a report: In a blink-and-miss-it move, the online retail giant quietly reduced its free shipping minimum rate to $35. The change was picked up and reported by a number of news outlets over the weekend, and was spotted by Fortune as well during the online checkout process. Amazon confirmed the change on its shipping guidelines and options page, designating which items and regions for delivery are eligible for free shipping. Amazon's free shipping rate, arguably one of the promotions on the site that has been the most popular and vaulted it to its e-commerce throne in years past, has gone up and down over the years. The free shipping minimum has been as low as $25 in the past and was most recently as high as $49.