Biodegradable vs. Compostable: What’s the Real Difference? (And Why It Matters)
by Kay Baker on Sep 21, 2025
Biodegradable vs. Compostable: What’s the Real Difference? (And Why It Matters)
You are in the store trying to make a good choice. One package says biodegradable. Another says compostable. They sound similar, yet they mean very different things once you look at the science and the rules behind the labels. Understanding that difference helps you avoid greenwashing and buy products that do what they promise.
What “biodegradable” really means
Biodegradable means microbes can break a material down under the right conditions. It does not guarantee how quickly that will happen, or that it will happen in places like landfills or the ocean. Many common materials — including glass, metals, and most conventional plastics — are not considered biodegradable in any practical time frame.
U.S. marketing rule of thumb: The FTC’s Green Guides allow an unqualified degradable claim only if the entire product will completely break down within about one year after customary disposal. Items typically sent to landfills, recycling facilities, or incinerators usually do not meet that bar, so unqualified “biodegradable” claims for them are considered deceptive.
What about that viral “plastic bottle takes 450 years” line? Real-world breakdown rates vary by environment and conditions, so simple, exact timelines are unreliable. In water, many plastics fragment into microplastics instead of fully biodegrading.
What “compostable” means
Compostable is more specific. It means the material will break down into usable compost safely and in a timely manner in the setting claimed — for example, an industrial composting facility or a home compost system — with no harmful residues.
In practice, North American certifications rely on standards such as ASTM D6400 and ASTM D6868. These require disintegration under controlled composting conditions and around 90% biodegradation within roughly 180 days in an industrial facility, plus eco-toxicity checks.
Home vs. industrial composting
Some certified compostable products only break down in industrial facilities with higher temperatures and controlled aeration. Others are designed for home compost and work at lower temperatures. Always check the label and local options.
How to shop with confidence
- Look for specifics, not vague claims. “Compostable in industrial facilities per ASTM D6400; certified” is meaningful. “Eco-friendly” or just “biodegradable” without context is not.
- Match the claim to your disposal option. If you do not have access to industrial composting, favor items that are recyclable where you live or truly home-compostable when appropriate.
- Remember that landfills limit decomposition. Do not assume “biodegradable” means it will break down there quickly.
Where Green Llama stands
We avoid vague environmental language and design for real-world end-of-life outcomes. When we make a compostability claim, we tie it to the correct setting and supporting standards. When we can remove plastic entirely, we do. If you ever have a question about a Green Llama material or label, ask us — we will show our work.
Packaging transparency: our refill packaging is engineered as a lamination of kraft paper, metallised cellulose, and PBS (polybutylene succinate). It is designed for home composting; formal home-compostable certification is not yet completed and is planned. Until certification is achieved, please follow local guidance and compost only where accepted.
FAQs
Can I home-compost this packaging today?
Our refill packaging is designed for home composting, but certification is pending. Because acceptance varies by location, please follow your local guidance and compost only where it is explicitly accepted. When in doubt, keep it out of the bin.
What does home-compostable certification involve?
Independent testing bodies evaluate disintegration and biodegradation in home-compost conditions and confirm no harmful residues using plant growth and eco-toxicity checks. We plan to complete certification and will publish the results.
What if my curbside compost does not accept packaging?
Many programs accept only food and yard waste. If packaging is not accepted, use trash or an industrial compost facility where available to avoid contaminating local streams.
Is this packaging recyclable?
Multilayer laminations like kraft paper / metallised cellulose / PBS are generally not curbside recyclable. Please follow local guidance.
Bottom line
- Biodegradable tells you it can break down, but not how fast or where.
- Compostable tells you it will break down safely and on a composting timeline in the specified setting, verified by testing standards and certifications.
References (for readers who want to dig deeper)
- FTC Green Guides – guidance on degradable and compostable marketing claims.
- ASTM D6400 / ASTM D6868 – specifications for labeling plastics designed to be aerobically composted.
- EPA resources distinguishing biodegradable vs compostable and compost system considerations.
- Regional facility finders and certification bodies for industrial composting and product certification.