Pizza Boxes Alternative ways to recycle Put in Garbage Cut Away Soiled Portions Any part of the pizza box soiled by food residue or grease is not recyclable and can contaminate other clean paper and cardboard. A clean, empty pizza box can be recycled with cardboard, so cut away all soiled portions, or just recycle the top half. Leftover Pizza and Crumbs Are Food Waste If you have any leftover pizza or crumbs, dispose of them with other food waste. LunaseeStudios / Shutterstock.com Frozen Pizza Boxes Contain Plastic Frozen pizza boxes aren’t just paper. They are lined with a layer or two of plastic to help keep preserve contents while frozen. Find out what to do with frozen food boxes. Alternative Ways to Recycle Use as Weed Prevention in Your Garden For any gardener preparing to battle weeds, laying down cardboard below the soil works as weed prevention, pizza boxes included. Did You Know? The Cost of Recycling the Pizza Box Greasy pizza boxes contaminate clean recycling and are expensive for the recycling industry: It’s estimated that contamination costs recyclers $700 million per year due to damaged machinery, the cost of disposing of non-recyclable materials and wasted time. What Came Before Pizza Boxes? Around two-thirds of all pizzas are delivered in pizza boxes. Pizzas first were delivered in wax-lined paper bags just like pies. Between World War I and World War II, they started being delivered in boxes made from corrugated cardboard like they are today.