Key points
- A COA without a lot number describes nothing you can verify.
- Method references are what make a value comparable and enforceable.
- Identical values across consecutive lots suggest transcription, not testing.
Minimum content
Producer and plant identity, product name, lot number, production date, quantity covered, each tested parameter with its result, unit, analytical method reference and specification limit, the testing date, and an authorised signature or issuing reference.
How to read one critically
Check that the lot number matches the packing list and packaging, that the parameters match your specification rather than the supplier's datasheet, and that the methods are the ones your contract names. Values quoted without units or basis are not usable.
Its limits
A COA reflects the sample the producer tested, not necessarily the cargo you received. It supports acceptance; it does not replace your own sampling and verification programme.
What to verify
- Lot number consistent with packing list, packaging and transport document
- Every contractual parameter present with method and units
- Testing date consistent with the production date
Risks to manage
- Generic datasheet supplied in place of a lot-specific certificate
- Parameters reported that differ from the contractual specification
- Results transcribed from a previous lot
Common mistakes
- Accepting a certificate without a lot number
- Filing the COA without reconciling it against your own results
- Treating the COA as a substitute for incoming testing
Terms used on this page
- COA
- Certificate of analysis — a lot-specific report of measured values against a specification.
Frequently asked questions
Should the COA come from an independent laboratory?
For routine trade a producer certificate is normal. Independent accredited results are usual for contested lots, high-risk contaminants or contractual dispute resolution.
What if the COA arrives after the cargo?
Sample and hold the lot pending the certificate. Accepting and commingling before the certificate arrives removes both the evidence and the remedy.
Related reading
Technical references
Need this applied to a specific purchase?
Send your requirement and we will structure the specification, supplier shortlist and verification plan around it.
Start a sourcing request