It's one of the most under-publicized policies of some of the biggest U.S. retailers: sometimes they give customers full refunds and let them keep unwanted items too. Returnless refunds are a tool that more retailers are using to keep online shoppers happy and to reduce shipping fees, processing time and other ballooning from mountains of returned products. Companies such as Amazon, Walmart and Target have decided some items are not worth the cost or hassle of getting back. Think a $20 T-shirt that might cost $30 in shipping and handling to recover. While the practice is not exactly a trade secret, the way it works is shrouded in mystery.

It's summertime, and the bargains seem easy at a time when many consumer prices are high. July sales events have become a seasonal revenue driver for the retail industry since Amazon launched its first Prime Day in 2015. While consumers may be enticed by the advertised can't-miss savings on some products, personal finance experts say shoppers should be careful not to fall for potentially misleading marketing or give in to impulse buys. Amazon is holding its 10th Prime Day event on Tuesday and Wednesday. Retail rivals like Walmart, Target, Kohl's, and newcomers TikTok Shop and Temu launched summer promotions ahead of Amazon, hoping to siphon off some of the e-commerce giant's savings-hungry shoppers.