Two claims that sound similar
A common question from packaging and product teams runs like this: if we buy plastic credits, can we say our packaging is recycled? The answer is no, and the reason matters for every sustainability claim a brand publishes. A plastic credit and a recycled-content claim measure different things. A plastic credit represents plastic waste that was collected or diverted, funded by the buyer and recorded in a registry. A recycled-content claim describes how much of the material in a product or package came from recovered waste. One is about the environment outside the product. The other is about the product itself.
What a plastic credit actually supports
A plastic credit is typically calculated at one kilogram of plastic waste collected or diverted. When a buyer retires the credit, the registry records that the volume has been claimed once. The credit supports statements about the buyer's plastic footprint, such as having funded the removal of an equivalent amount of plastic from the environment. It does not travel with a unit of product, and it does not change the material the product is made from.
That is why a credit is best understood as a footprint instrument, alongside measurement and reduction, rather than as a material input. The distinction is explored in more depth in the article on plastic neutrality versus plastic-free claims.
How recycled content is measured
Recycled content has its own vocabulary. Post-consumer material is recovered from products after use by consumers and businesses, such as bottles collected through a deposit scheme. Pre-consumer material is scrap generated during manufacturing that is reprocessed rather than sent to waste. Each category requires different evidence, and a claim that does not specify which one applies is weaker than it looks.
Physical content is the most intuitive measure. Where recycled and virgin material are kept separate through the process, the share in each batch can be tracked directly. Many production routes do not allow this. Recycled flakes, pellets or feedstock are often blended into large processing streams, which makes physical tracing impractical.
What mass balance does and does not prove
Mass balance is the accounting method that fills this gap. Under a chain-of-custody certification such as ISCC PLUS, recycled input is tracked through the supply chain and then allocated to a set of outputs, even though the physical molecules are not separated. The allocation is documented and audited, and the certificate states what share of output may be sold with a recycled claim.
The important point is what the claim refers to. A mass-balance claim describes an allocated share of production, not the recycled content of every unit on the shelf. Responsible brands state this clearly, name the certification, and avoid language that implies each item is physically recycled. Mass balance is also distinct from plastic credits: it documents the flow of recycled material through a production system, while a credit documents the removal of waste from the environment.
Where plastic credits fit in a strategy
The two instruments can sit in the same plastic strategy because they address different parts of the problem. Reduction and redesign come first, since they lower the amount of plastic a business uses. Recycled content addresses the material in products that still need plastic. Extended producer responsibility obligations address the collection and recycling duties that apply by law. Plastic credits can then cover a residual footprint that remains after those steps, with the claim worded to say exactly that.
A simple test helps. If a statement would still be true when the credits are removed from the story, it is probably a claim about the product. If it becomes false without the credits, it is a claim about the footprint.
Wording that holds up
Consider a bottle brand that buys credits equal to the plastic it sells each year. It can say that it has funded the collection of an equivalent amount of plastic waste, and that the credits are retired in a named registry. It cannot say the bottle is made from recycled plastic unless recycled content is documented separately. If the brand also uses recycled resin under mass-balance certification, the two claims should appear as separate statements, each with its own evidence and its own wording.
Avoid blended phrases such as 'plastic-neutral recycled packaging' that merge the concepts. Readers and auditors will take that phrase to mean the product contains recycled material that has been offset, which is rarely what the evidence supports.
Questions to ask before publishing
- Which claim does the evidence support? Name the credit, the recycled content or the mass-balance allocation, and keep them separate in the wording.
- Which certificate sits behind the recycled claim? Ask for the chain-of-custody certificate and check its scope and validity dates.
- Would the claim still be true without the credits? If not, it describes the footprint, not the product.
- Does the claim say what the percentage refers to? A share of output allocated by mass balance is not the same as a share of every unit.
- Has legal or sustainability review seen the final wording? The rules on environmental claims differ by market, and the safest wording is the one a regulator would read the same way.
About the author
Plastic Units editorial team
Editorial team
The Plastic Units editorial team writes and maintains the Knowledge Bank and news on the plastic credits market, recycling economics and plastic policy.