Biodegradable and Compostable Poop Bags: What the Labels Mean

A “biodegradable” poop bag that goes in the trash does not do what the word suggests. The US Federal Trade Commission told sellers as much: most waste bags end up in landfills, where no plastic biodegrades in anywhere close to one year, if it biodegrades at all. A certified compostable bag is a real thing, but it only composts in a facility that takes pet waste, and few do. For most owners the useful choices are a bag made with recycled plastic, a bag that does not tear, and picking up every time.

This guide applies to any size of dog, from the biggest dog breeds down.

What the Words Mean

Biodegradable. With no qualification, the FTC says shoppers take it to mean that the product will completely break down into natural components within one year of ordinary disposal. For a bag thrown in the trash, that is not what happens. In February 2015 the agency’s staff sent warning letters to 20 makers and sellers of dog waste bags over exactly this claim.

Compostable. A narrower, testable claim. In North America the standard is ASTM D6400 and in Europe EN 13432; both are about industrial composting plants, not a heap in the garden. The catch is in the same FTC letter: dog waste is not safe for home composting, and very few facilities accept it.

Recycled content. Still plastic, but made partly from plastic that has already been used once. It makes no claim about breaking down.

Oxo-degradable. Plastic with additives that make it fragment. The European Union no longer allows products made of oxo-degradable plastic to be placed on its market; that rule has applied since 3 July 2021.

Where the Bag Actually Goes

In the trash, it goes to landfill or incineration, and the bag’s material makes little difference to what happens next.
In a green bin, only if your program says it takes pet waste - most do not. Even a maker that sells compostable bags says plainly that municipal green bin programs rarely accept dog waste.
In a home compost heap, no. See below.

So before paying extra for compostable bags, ask your waste service one question: do you accept pet waste, and in which bags?

Certified Compostable Bags

A bag sold as certified compostable should name its standards - the European EN 13432 and the US ASTM D6400 - and a certification body such as BPI, often with a certificate number, as one maker does. That is a certification about the material in an industrial composting plant.

One large maker of dog waste bags sells two kinds of bag and is unusually frank about the difference. According to the maker, its standard bags are 15 microns thick and made from 65% certified post-consumer recycled plastic. Its compostable line is 18 microns and certified for industrial composting - and the company adds that the facilities to compost pet waste exist in only a small number of cities, so most owners in North America cannot use those bags as intended.

If Your Waste Goes to Landfill

Then a compostable bag has little to offer, and the practical choices are:

Recycled-content bags, which at least use less new plastic.
A bag thick and large enough that you never need a second one.
No bag wasted: one bag per pick-up, tied shut.

Carrying Bags

The bag you have with you is the one that gets used. A dispenser on the leash solves that.

Other Ways to Dispose of Dog Waste

A brochure from the Mid-America Regional Council, carried in the US Environmental Protection Agency’s outreach library, lists three:

Trash, wrapped carefully so that it does not spill during collection.
Flush the waste itself down the toilet, so that it is treated at a sewage plant. The waste, not the bag.
Bury it in your own yard, at least 12 inches deep, in several different places and away from vegetable gardens.

The same brochure explains why picking up matters at all: left on the ground, pet waste is washed into storm drains and on into streams untreated, carrying bacteria and nutrients with it. It also says outright that pet waste is not a fertilizer.

Composting at home

Do not put dog waste on a compost heap that feeds a garden. The FTC’s letter describes dog waste as not safe for home composting. If you garden with pets around, our list of pet-safe plants covers what is safe to grow.

Frequently Asked Questions

What is the difference between biodegradable and compostable?

“Biodegradable” on its own promises more than a bag in the trash can deliver, according to the FTC. “Compostable” refers to a tested standard for industrial composting.

Do biodegradable bags break down in landfill?

The FTC’s answer: no plastic biodegrades in a landfill in anything close to a year, if at all.

Are compostable bags worth the extra cost?

Only if a composting program near you accepts pet waste in those bags. Ask before you buy.

Can I compost dog waste at home?

Not for use on a garden. Trash, flushing the waste itself, or burying it away from vegetables are the options in the brochure above.

Can I flush a poop bag?

No - flush the waste only, unless a bag is specifically sold as flushable and your plumbing and local rules allow it.

Are oxo-degradable bags a good choice?

The EU has not allowed products made of oxo-degradable plastic on its market since July 2021.

How should I store compostable bags?

Somewhere cool, dry and dark, and use them within the period the maker gives - they are designed to break down.

Final Word

Read the claim, then check where your trash goes. Unless a local program composts pet waste, a compostable bag ends up in the same landfill as any other, and a sturdy bag with recycled content is the honest choice. What matters most is the part that is not about the bag: pick it up, every time.

Litter Box Hygiene Guide
Pet Odor Removers: Enzyme Cleaners and How to Use Them Last updated: October 2026.