Rakuten is currently offering up to 5% in-store card-linked cashback at merchants including Best Buy, Nordstrom, Office Depot/Max, Walgreens, and Walmart. All you need to do is link the credit card you plan to use in Rakuten, then use that card at the corresponding physical store. Rakuten will automatically track your purchase amount and award cashback. This cashback does not conflict with the cashback or rewards earned from your credit card itself, so you can stack both. In short, if you link your card, it’s basically free extra cashback, and 5% is pretty solid.

The terms usually say that gift card purchases are not eligible, but in practice, if you buy them together with other items, they can often still go through...