Seattle is an iconic American city; from fish markets to frappuccinos, it’s often been at the forefront of culture. It’s also long been at the forefront of sustainability, particularly when it comes to recycling and composting. In 2005, Seattle became one of the first cities in the U.S. to offer curbside composting services to its residents. By 2009, Seattle required all residents to either enroll in the curbside composting program or compost in their backyard, and by 2015, the city had totally banned organic waste from garbage bins. 

These policies led to a significant reduction in garbage disposal volume and helped to divert thousands of tons of organic waste from landfills. Today, the curbside composting program is still in full effect — if you want to know more about how to compost in Seattle (and what you can and can’t include in your compost bins), read on.

Seattle municipal composting rules

Like most cities, Seattle residents use one bin for both food scraps and yard waste, which is collected weekly alongside trash and recycling. The city makes garbage day easy by collecting everything at one time; however, it’s essential to know what does and doesn’t belong in Seattle’s green bins. 

What you can compost in Seattle

Seattle’s system can handle meat and dairy, as well as boxes and paper products, thanks to its industrial composting facilities. You can find a full list of what is and isn’t compostable here on the city’s official website. Some highlights for what you can compost in Seattle include: 

• Almost all food. If you eat it, it can probably be composted through Seattle’s curbside composting program. This includes fruits, vegetables, meat (including bones), fish, dairy, bread, grains, eggshells, and coffee grounds. 

• Food-soiled paper. Paper items like napkins, paper towels, coffee filters, and uncoated pizza boxes are all acceptable. Just make sure you avoid anything with a shiny or plastic coating.

• Compostable bags and boxes. Certified compostable bags and containers can go into the bin, as long as they’re clearly labeled as BPI.

• Yard waste. Leaves, grass clippings, branches, and other yard debris are welcome.

What you can’t compost in Seattle’s curbside program

While Seattle’s composting program is comprehensive, there are a few things that should stay out of your composting bin. If you’re unsure, Seattle Public Utilities provides a detailed list. Here are the basics:

• Cooking oil and grease. These can cause problems in the composting process, so while small amounts of grease on a pizza box are fine, large amounts are not. Don’t dump oil into your compost bin or bags of food scraps.

• Food stickers. Make sure you always remove stickers from produce before composting.

• Plastic. Unfortunately, plastic lasts forever and is therefore not compostable. 

• Pet waste and rocks. These materials don’t break down properly. They can contaminate the compost and should be kept out of compost bins. 

How to start curbside composting in Seattle

If you’re new to Seattle or need to start composting services, you can sign up and enroll through Seattle Public Utilities (SPU). When you request a bin from SPU, you can choose from several sizes based on your household’s needs. If you already have a bin but it’s been damaged, or you need a different size, you can replace or resize your bin through the city’s official government site.

Once you sign up, your food and yard waste will be collected weekly, and you can check your collection day on the city’s website. While you don’t need to line your outdoor bin, using paper or certified compostable bags in your indoor compost container can make cleanups easier and reduce odors. Make sure you use an approved compostable bag and avoid plastic, as it’s not compostable. 

If you want to supplement Seattle’s curbside compositing or just take fewer trips to the curb, Mill can help. The Mill food recycler can process everything from apple cores and banana peels to chicken wings and stale bread. Mill turns uneaten food into Food Grounds that can then be added to your curbside compost bin. Plus, it dehydrates and dries the grounds, keeping your kitchen free of fruit flies and unpleasant smells. 

How to get compost in Seattle

Seattle’s robust composting system doesn’t just help you reduce food waste — it also gives back to the community in the form of nutrient-rich compost. So, if you’re looking to get free compost from your community’s program, Seattle is the place to do it. 

Seattle Public Utilities (SPU) partners with community organizations all year to host events where they give away free bulk compost. These events are BYOB (bring your own bucket) and BYOS (bring your own shovel), so if you’re looking for compost, just make sure you come prepared.

Outside of these events, you can also consider getting compost from private suppliers like ZooDoo, a Seattle favorite made from animal manure at Woodland Park Zoo. It’s a unique and eco-friendly way to enrich your garden; just know that it isn’t kitchen scrap compost. You can also check with local gardening centers or composting events to see if municipal compost is available for purchase.

Another option for bulking up your backyard compost pile? Mill Food Grounds. Rather than sending them to curbside pickup, you can layer these into your backyard compost pile as green material. Thanks to their small size, the grounds will break down faster than unprocessed food scraps.

Sources:

1. Seattle Public Utilities: “Food Waste Requirements.” https://www.seattle.gov/utilities/your-services/collection-and-disposal/food-and-yard/food-waste-requirements

2. BioCycle: “Seattle’s Winning Strategy For Managing Organics.” April 14, 2020. https://www.biocycle.net/seattles-winning-strategy-managing-organics/

3. Seattle Public Utilities: “Compost Right. It Matters.” https://www.seattle.gov/utilities/your-services/collection-and-disposal/food-and-yard/compost-right

4. Seattle Public Utilities: “Beyond the Cart.” January, 2024. https://www.seattle.gov/documents/Departments/SPU/Services/Recycling/WDIG/Sorting-Compost-Recycling-Garbage-English.pdf

5. Seattle Public Utilities: “Compostable Bags.” https://www.seattle.gov/utilities/your-services/collection-and-disposal/food-and-yard/compostable-bags

6. Woodland Park Zoo: “Zoo Doo Compost.” https://www.zoo.org/zoodoo