Batch Number vs. Lot Number: What's the Difference?
A batch number and a lot number both identify a group of products that share the same origin, so they can be traced and recalled together. In regulations and on product labels, the two terms are usually treated as synonyms. In inventory and production systems, however, they are often kept apart: a batch is the output of one production run, while a lot is a quantity of identical product that is stored and traded as one unit. A batch can be split into several lots, but a lot never contains more than one batch.
How regulators and standards define the terms
Official definitions rarely separate the two words - in fact, they often define one with the other:
EU GMP guidelines (EudraLex Volume 4) define “Batch (or lot)” as a defined quantity of starting material, packaging material or product processed in one process or series of processes so that it can be expected to be homogeneous.
Directive 2011/91/EU on food lot marking defines a lot as “a batch of sales units of a foodstuff produced, manufactured or packaged under practically the same conditions”.
The Codex Alimentarius defines a lot as a definitive quantity of a commodity produced essentially under the same conditions.
GS1 barcodes use one Application Identifier, AI (10), for “batch or lot number”.
So if a customer, an auditor or a label says “batch” or “lot”, they usually mean the same thing: a group of products that can be traced as one.
The practical difference in inventory and production
The distinction becomes useful once you start managing stock. Many ERP systems - and this dictionary - use the following definitions:
Batch
Lot
What it is
The output of one production run
A quantity of identical product handled as one unit
Where it comes from
Your own production
Production, purchasing or splitting an existing lot
Typical identifier
Production order number, brew number, best-before date
Lot number assigned at receipt, production or repacking
Can it be split?
Yes, into several lots
Yes, into new lots with new lot numbers
Can it be combined?
-
No, a lot never contains more than one batch
The key point is that every batch becomes at least one lot, but not every lot comes from a batch. Goods you buy and resell, for example, get a lot number at receipt without ever having been a batch in your own production.
Examples
Brewery. Brew no. 112 produces 2,000 litres of beer - that is one batch. Half is bottled and half is filled into kegs. The bottles and kegs become two separate lots, each with its own lot number, but both refer back to batch 112.
Importer. A coffee importer receives a container of green coffee beans from a supplier. The delivery is registered as one lot with the supplier’s lot number. There is no production batch involved.
Pharmaceutical distributor. A distributor receives a medicine with the manufacturer’s batch number printed on the packaging. That batch number follows every unit through storage and delivery, and the distributor must be able to say which customers received which batch.
Why the distinction matters
Keeping batch and lot apart gives more precise traceability. If a quality problem is found in the kegs from brew 112, but the bottles were filled on a different line, the brewery can recall only the keg lot. If batch and lot are treated as one, the whole batch has to be recalled.
It also matters for stock with different properties. If part of a batch is stored under different conditions, gets a different best-before date or is repacked into another unit of measure, it should become its own lot.
Some companies get by without the distinction, typically when every production run is sold as one unit. But it is easier to separate the two from the start than to introduce the distinction later.
Batch and lot numbers vs. serial numbers
A serial number identifies one single unit, while batch and lot numbers identify a group. In the EU, prescription medicines must carry a unique identifier under Delegated Regulation (EU) 2016/161, which includes both a serial number and the batch number. In food, serial numbers are rare - lot-level traceability is the norm.
Frequently asked questions
Is a batch number the same as a lot number?
On labels and in most regulations, yes. In inventory and production systems, a batch usually refers to one production run, while a lot is a quantity of identical product that can come from production or purchasing.
Can a lot contain several batches?
Not if you want precise traceability. If products from two batches are mixed into one lot, you can no longer tell them apart in a recall. Instead, a batch is split into several lots when needed.
Can the best-before date be used as a lot number?
For food in the EU, yes. Directive 2011/91/EU allows the lot marking to be left out if the best-before or use-by date shows at least the day and month. Many producers therefore use the date as their lot identifier.
Where do I find the lot number on a product?
On food, the lot number is usually printed near the best-before date and often starts with “L”. On medicines, it is marked as “Lot”, “Batch” or “Ch.-B.” and is also encoded in the 2D barcode.
