How to Verify a Compostable Certificate
Table of Contents
A Practical Verification Guide for Buyers and Importers
Compostable certificates are now widely used in packaging, especially for trash bags, liners, mailers, and food-contact packaging.
But in real sourcing situations, one problem appears again and again:
Having a certificate does not always mean the product is compliant.
Many buyers discover issues only after goods arrive — during customs clearance, retail onboarding, or audits by composting facilities.
This guide explains how to verify a compostable certificate step by step, using official databases and simple checks that any buyer can apply.
No marketing language.
No assumptions.
Only verification.
Why Compostable Certificates Are Often Misunderstood
Most sourcing mistakes happen because buyers assume:
A PDF certificate is enough
A company-level certificate applies to all products
A compostable logo automatically means compliance
“Biodegradable” and “compostable” are the same
In reality, compostable certification is product-specific, scope-limited, and time-bound.
If a claim is incorrect, the importer or brand usually carries the risk, not the factory.
That is why verification matters.
Step 1: Identify What Type of Compostable Certificate You Are Reviewing
Before checking anything, you must first identify which certification system applies.
Common compostable certifications include:
North America
BPI Certification (ASTM D6400 / D6868)Europe
EN 13432 (issued by different notified bodies)OK compost
OK compost INDUSTRIAL / OK compost HOME (TÜV Austria)Australia / New Zealand
AS 4736 (industrial) / AS 5810 (home)
Each system has its own rules, databases, and scope limits.
If a supplier cannot clearly explain which certification they are using, that is already a warning sign.
Step 2: Request the Full Certificate — Not Just a Screenshot
Always request the complete certificate document, not cropped images or logos.
At minimum, the certificate should clearly show:
Certificate number
Issuing organization
Certified company name and address
Product name or product scope
Applicable standard
Issue date and expiry date
If the supplier hesitates or only sends a logo image, verification is not possible.
Step 3: Check the Certificate in an Official Database
A compostable certificate must be traceable in an official database.
This is the most important verification step.
Examples include:
BPI certified product database
TÜV Austria OK compost database
Certification body listings for EN 13432
Regional verification programs for AS 4736 / AS 5810
If the certificate number or company name does not appear in the official database, the claim should be treated as unverified.
A PDF alone is never enough.
Step 4: Confirm the Certification Scope Matches the Product
This is where many sourcing errors happen.
You must confirm that the certificate scope matches:
The actual product type (bag, liner, film, packaging)
The material structure (not only resin)
The intended use (industrial vs home composting)
The product format (printed, multilayer, thickness range)
Common misuse includes:
Resin certificates used to claim finished-product compliance
One certified item used to sell multiple uncertified products
Industrial compostable certificates used to imply home compostability
If the product you are buying is not clearly listed in the scope, it is not covered.
Step 5: Check Certificate Status and Validity Dates
Compostable certificates can expire, be suspended, or be withdrawn.
Always check:
Is the certificate currently valid?
Has it passed its expiry date?
Is the status marked as active in the database?
Some suppliers continue to show certificates that expired years ago.
If the certificate is no longer valid, the compostable claim should not be used.
BioAbfallverordnung (BioAbfV) & Annex 5 Explained
Germany’s BioAbfallverordnung (BioAbfV) includes specific rules for biowaste collection bags.
Annex 5 of this regulation defines how compostable biowaste bags must be labeled, including the use and presentation of the Seedling (Keimling) logo. Only bags that meet these labeling requirements may be considered suitable for certain biowaste collection systems.
This regulation highlights the difference between:
- General compostable packaging
- Compostable bags intended specifically for biowaste collection
Step 6: Verify Logo and Label Usage Rights
Certification logos are licensed, not decorative.
Proper verification includes checking:
Whether the certified company is authorized to use the logo
Whether the logo version matches the certified standard
Whether the logo is used only on certified products
Misuse of compostable logos is a common compliance issue and can lead to product rejection by retailers or composting facilities.
Common Red Flags Buyers Should Watch For
Be cautious if you see any of the following:
Certificate without a verifiable database entry
Certificate issued for raw material only
No clear product scope or model reference
EN 13432 used to claim home compostability
Expired or undated certificates
Mismatch between certificate holder and supplier name
Generic “biodegradable” claims instead of certified compostable
These are typical signs of greenwashing or misrepresentation.
A Simple Verification Checklist Buyers Can Reuse
Before approving any compostable packaging, confirm that you have:
Full certificate PDF
Official database link showing active status
Product scope matching your exact item
Valid dates and issuing body
Approved logo usage confirmation
If any item is missing, verification is incomplete.
Next Step: Verify by Certification Type
This page explains the general verification framework.
For standard-specific verification, use the dedicated guides below:
- How to Verify an EN 13432 Certificate
- How to Verify an OK Compost Certificate (HOME & INDUSTRIAL)
- How to Verify a BPI Compostable Certification
Each guide walks through the exact database, numbering system, and common misuse patterns for that standard.
Final Note for Buyers
Do not rely on logos, claims, or sales explanations.
A compostable certificate is only meaningful if it can be independently verified.
Verification protects your supply chain, your brand, and your customers.
