Pizza boxes are corrugated cardboard with grease and, often, stuck-on cheese. Some paper mills will take a greasy empty box. Some will not. A city that changed its rule this year is not a rule for the rest of the country.
Photo: A slice of pizza in a cardboard pizza box. Nenad Stojkovic, 2019-08-05. CC BY 2.0 · Source. Resized for web.
Portland, as a worked example
Portland Bureau of Planning and Sustainability announced the change on June 15, 2026:
- Recycle empty pizza boxes. Grease is allowed.
- Remove paper liners and plastic pieces. Those go in the trash.
- Remove leftover food.
- A box with cheese or sauce still stuck to it goes in the residential compost cart, or in the trash if the household has no compost service.
- Frozen-pizza boxes go in the trash.
The change tracks Oregon’s Recycling Modernization Act. It applies to Portland residential recycling, not to every U.S. city that happens to have a blue cart.
City page: Portland, Oregon. Program: Portland Bureau of Planning and Sustainability. State hub: Oregon.
How to read any other city
Look up the local accepted-materials list. If the city is silent, treat the box as trash or ask the official lookup — do not copy Portland’s sentence onto an Austin or Boston page.
Empty the box. A liner, a plastic “table,” a garlic-butter cup and leftover crusts are not cardboard.
Start at States & Cities and open the edition for your address.
Sources: Portland recycling update.
