All steel and plastic travel mugs, plastic bottles, ceramic mugs, as well as glass products should only be hand washed. It is not recommended to wash these products in a dishwasher as this will promote fading (and gradual loss) of the imprint. We recommend hand washing because the imprint lasts longer. If products are the dish washed imprint fading may occur. Restaurant grade mugs are dishwasher safe as they are Hardwearing & won't chip easily. Overall we recommend hand washing all drink ware.