Costco Diaper Sale 2025. The kirkland brand costco diapers really only go on sale 1x per year so if you need some, i would stock up! Diapers at costco go on sale in a cyclical pattern, but you may see deals on some brands more often than others.

You can order them online too for the same price and free shipping Costco (cost) switching its diaper producer from kimberly.