It Varies Significantly by Program

Some programs require compostable bags (Minneapolis). Some accept BPI-certified bags (Kansas City). Chicago explicitly bans all bags including compostable ones. NYC's community garden drop-offs don't allow them; smart bins do. Know your program's rule before buying bags.

Programs That Require Compostable Bags

Minneapolis requires scraps to be brought in compostable paper or certified compostable plastic bags. Loose scraps are not accepted. This is the opposite of Chicago's approach and worth knowing before your first Minneapolis drop-off.

Programs That Accept BPI-Certified Bags

Kansas City accepts BPI-certified compostable bags. Look for the BPI logo and a bag that's soft to the touch (not crinkly). If the bag doesn't have BPI certification visible, don't assume it qualifies — the KC program's rule is "when in doubt, throw it out."

Programs That Ban All Bags

Chicago's citywide program bans all bags — paper, compostable, and plastic. Empty your scraps directly into the cart and take your container home. If you used a liner bag, remove it and dispose of it in a regular trash can at the site (not in the compost cart).

What Is BPI Certification?

BPI (Biodegradable Products Institute) is the main U.S. certification body for compostable products. BPI-certified bags meet ASTM D6400 or D6868 standards — they're verified to break down in commercial composting conditions within 84 days.

Many bags labeled "compostable" or "biodegradable" are not BPI-certified and may not break down in composting conditions. The BPI logo is the reliable indicator.

The General Rule

If you're not sure whether your program accepts bags: don't use one on your first visit. Bring scraps in a reusable container and empty them directly. Once you've confirmed what's accepted at your specific site, decide on a bag strategy from there.

Frequently Asked Questions

It comes down to how material is processed at the receiving facility. Some commercial composting operations can handle BPI-certified bags and process them successfully. Others — including the facility that receives Chicago's material — prefer to avoid bags entirely to maintain consistent compost quality. The facility's specifications drive the drop-off program's bag rules.
Some programs (Minneapolis, certain community garden programs) accept plain uncoated brown paper bags as a compostable liner. Bags with glossy printing, wax coating, or plastic handles may not be accepted. When in doubt, stick with BPI-certified compostable bags or no bag at all.