Guide ยท Traceability
Batch and lot numbers: tying the CoA to the delivery
- Short answer
- A batch or lot number identifies one quantity of material expected to be uniform within specified limits. For traceability, the number on the CoA, on the container label and on the delivery note should be the same, and recorded exactly as printed. If they differ, treat the certificate as not yet applying to the goods until the supplier explains why.
General background, not regulatory or GMP advice. Definitions and record requirements differ by sector and jurisdiction; follow your own procedures.
What the number is for
Guidance and regulation treat batch and lot as near-synonyms. ICH Q7 defines a batch (or lot) as a specific quantity of material produced so that it is expected to be homogeneous within specified limits, and a batch number as a unique combination of numbers, letters or symbols from which its production and distribution history can be determined. US drug GMP regulations (21 CFR 210.3) define a lot number in much the same way. Some companies use batch for the production quantity and lot for a portion of it, so check what your supplier means.
The number is the thread that ties a certificate to physical goods. When a complaint, a failed result or a recall arises, it is how you find what was received, what it was tested against and where it went. A certificate showing a different lot from the drums says nothing about the drums, and one naming only an order cannot be tied to a lot at all: see CoA vs certificate of conformance.
Tying the documents together
A routine for each delivery.
Read the lot from the container
Take the number from the label on the container itself, not only from the delivery note. Record it exactly as printed, including letters, hyphens and leading zeros.
Match it to the certificate
Compare character by character. Watch for O and 0, I and 1, a suffix such as -A, and a different format. Then check the other header fields: product, grade and dates.
Match it to the delivery note and the order
The delivery note or packing list should show the same lot, product and quantity as the order. A transport document may show only a shipment number.
Count the lots
Several lots on one delivery need one certificate each. A certificate covering a blend, a composite or 'lots 1 to 5' needs the supplier to say how the lots were combined.
Follow the chain through a distributor
A distributor's own lot number should be tied to the manufacturer's lot on the certificate. Ask for the original manufacturer's certificate if it is not shown.
Record both numbers
Log the supplier's lot against your own receipt or control number, with the certificate number and dates, and keep the link if you split, repack or blend. See the review checklist.
Where a lot number appears and what to check
Not every document carries one. Small mismatches happen; unexplained ones should not pass.
| Document | What it usually shows | Check |
|---|---|---|
| Container label | The manufacturer's or packer's lot, sometimes both | Same as the certificate; legible; not overwritten |
| Certificate of analysis | The lot of the tested material, with dates | Matches the label; dates plausible; certificate number present |
| Delivery note, packing list | Lot per line, quantity, product code | Matches label and order; one line per lot |
| Bill of lading, consignment note | A shipment or container number, rarely a lot | Do not use as lot evidence |
| Purchase order, invoice | Product and quantity, sometimes a lot | Ordered grade and specification revision |
| Distributor's documents | Their own lot, or a relabelled one | A reference to the manufacturer's lot and certificate |
| Your receiving record | Supplier lot plus your control number | Both present; certificate attached |
What goes wrong with lot numbers
- A near miss treated as a match. One transposed digit means a different lot, or a typing error the issuer should correct, not you.
- A packing lot against a manufacturing lot. A supplier may certify the manufactured batch while the container carries a filling lot. Both can be valid, but the link has to be documented.
- A distributor relabel. A new lot number with no reference to the manufacturer breaks the chain to the testing laboratory.
- One certificate for many lots. Unless the supplier explains the combination, the results may describe only part of the material.
- A number fixed by hand. Correcting a lot number on a certificate yourself makes the document yours, not the supplier's. Ask for a corrected certificate.
- Numbers that recur. Some suppliers restart numbering by year or site, so pair the lot with product and dates.
How CertiClean helps
CertiClean reads the batch or lot number from the certificate header, under labels such as Batch, Lot and Charge, shows it in the batch header card, and repeats it on every row of the parameter CSV and in the batch log line, so each result stays tied to its lot in a spreadsheet. If no lot is found, a note says so and the lot stays empty. It never sees your container label or delivery note, so matching the lot to the goods stays with you. See CoA to Excel and pricing.
Free allowance: 1 file per day, up to 10 pages, no account.
Questions people ask
Is a batch number the same as a lot number?
Often, yes. ICH Q7 defines batch (or lot) as one term. Some companies use batch for the production quantity and lot for an identified portion of it, so ask your supplier what they mean.
What if the lot on the CoA differs from the container label?
Hold the material and ask the supplier to explain in writing. Possible reasons include a packing lot, a distributor relabel or a typing error. Do not assume which, and do not correct the document yourself.
Can one CoA cover several lots?
Sometimes, for a blended or composite lot, but each lot normally has its own certificate. If one certificate lists several lots, ask how the results relate to each lot.
Which lot number should I record?
The supplier's lot exactly as printed, with your own receipt or control number if you assign one. Record the certificate number too, so the three can be matched later.
Does a distributor need to show the manufacturer's lot?
Good practice says yes. Guidance for active ingredients expects a re-issued certificate to name the original manufacturer and refer to the original batch certificate.
How do lot numbers help in a recall or complaint?
They let you find what was received, which certificate described it, what it was used in and where it went. Without a reliable match you cannot say what was affected.
What does Charge mean on a certificate?
It is the German word for batch or lot, so Charge or Chargen-Nr. on a German-language certificate is the batch number. Other languages use lote, lotto or lot.
Should I keep the case and punctuation of a lot number?
Yes. Record the characters as printed, including hyphens, slashes and leading zeros. Normalising a number can break a later match with the supplier's documents.