A compostable label that does not name its standard is not a compostable label. It is a claim. The difference matters because UK and EU regulators, retail buyers, and waste operators all now require that compostability statements on packaging are backed by identified, independently verified standards before they are treated as credible. Printing the word “compostable” on a biodegradable label without specifying the standard to which that compostability has been tested is, in the CMA’s established view, an incomplete and potentially misleading environmental claim.
The standards that govern compostable packaging labels are not interchangeable, and choosing the wrong one for the claim being made is a common and consequential error.
EN 13432: The Industrial Compostability Standard
EN 13432 is the European harmonised standard for compostable packaging in industrial composting systems. It sets four core test criteria: at least 90% of organic material must convert to carbon dioxide within six months under controlled composting conditions; the material must disintegrate so no more than 10% of original mass remains as fragments larger than 2mm after the test period; there must be no negative effect on the composting process; and heavy metal content must remain within prescribed limits. The controlled conditions EN 13432 tests against, temperatures between 55 and 60 degrees Celsius with regulated oxygen and moisture levels, are those found in commercial composting facilities, not domestic garden bins.
Certification to EN 13432 is available through two principal bodies recognised in the UK: Din Certco, which issues the Seedling logo, and TÜV Austria, which issues the OK Compost Industrial certification. Both certifications confirm industrial compostability only. A label carrying the Seedling logo or OK Compost Industrial mark without additional qualification is not making a home compostability claim.
The Home Compostability Standard
Home compostability is tested to different standards that simulate the lower temperatures and longer timescales of domestic composting. TÜV Austria’s OK Compost Home certification tests biodegradation at temperatures up to 25 degrees Celsius over a twelve-month period, compared to six months at elevated temperatures under EN 13432. The parameters required to achieve OK Compost Home certification are substantially more demanding than EN 13432, because domestic composting conditions are less controlled and generate less sustained heat.
The EU PPWR, which applies generally from August 2026, requires that where packaging is only suitable for industrial composting, that limitation must be made clear on the label. It also triggered an obligation for the European Commission to request updated harmonised home compostability standards from standardisation bodies by February 2026, reflecting the growing regulatory interest in distinguishing the two types of claim.
What the Label Must Say
A compliant compostable label must specify whether the claim applies to industrial or home composting, name the standard or certification scheme that has been assessed, confirm that the certification covers the finished label in its complete form including adhesives and inks, and make the disposal route sufficiently clear that a consumer can act on it accurately. A label that carries “compostable” without any of that context invites both regulator challenge and retail delisting. The ASA has already upheld complaints against brands carrying unqualified compostable claims on household products, finding that consumers reasonably interpret such claims as meaning home compostability.