Pharmaceutical Serialisation: How It Works and Why It Matters

Pharmaceutical serialisation gives every saleable pack its own identity. Not a batch identity shared with 200,000 other cartons, but a number belonging to that carton alone, printed on it, recorded in a database and checkable at any point between the packing line and the patient.

The mechanics are well established. What changes is which markets require it, in what form, and with what data attached. That is what catches UK exporters out: the UK no longer has a mandatory scheme while most of its export markets do.

How pharmaceutical serialisation works

Generating and managing the numbers

Serial numbers are generated by the brand owner's enterprise system or by the packing site, then issued to a packing order as a controlled range. Numbers are usually randomised rather than sequential, so a counterfeiter holding one valid pack cannot predict the next.

Number management is a quality activity in its own right. Ranges must not overlap between sites or orders, unused numbers must be returned or retired, and every number issued must be accounted for as commissioned, shipped, destroyed or never used. Serial reconciliation sits alongside physical reconciliation of components at the end of a run.

The 2D DataMatrix and GS1 application identifiers

The carrier is almost always a GS1 2D DataMatrix, which holds a lot of data in a small area and reads reliably even when partially damaged. The data is structured using application identifiers, each a numeric prefix telling the scanner what the following characters mean.

A US DSCSA pack requires four: (01) the 14-digit GTIN, (17) expiry as YYMMDD, (10) lot number and (21) the unique serial number. EU FMD packs use the same building blocks, with the national reimbursement number added where a market requires it. Human-readable text alongside the code repeats the information for anyone without a scanner.

Print size is a genuine design constraint. A DSCSA DataMatrix is typically around 5 x 5 mm at minimum, and it must sit on a carton panel alongside Braille, a tamper seal and statutory text.

Printing, vision verification and grading

Codes are applied inline by thermal inkjet, continuous inkjet or laser, then verified by a camera immediately downstream. The camera decodes the code to confirm the content matches what the system intended to print, and grades print quality.

Grading follows ISO 15415 for 2D symbols, scoring contrast, modulation, fixed pattern damage and axial non-uniformity, then reporting an overall grade from A to F. Grade B or better is the common commercial expectation. A code that decodes on a new scanner at the line but grades D will fail downstream on a worn handheld, so grading predicts real-world readability rather than best-case readability. Failed packs are rejected automatically, and the reject station is itself a controlled point.

Commissioning and decommissioning

Commissioning is the moment a serial number becomes live: printed, verified and recorded as belonging to a real pack of a specific product, lot and expiry. Decommissioning marks the number as no longer valid for supply. Packs are decommissioned when dispensed, destroyed, exported out of the scheme, sampled, stolen or reworked.

Rework is where most data trouble originates. If a pack is opened, relabelled or re-cartoned, its original serial has to be retired and a new one commissioned, with the relationship documented. Central Pharma manages reworking data in-house alongside the physical rework, which keeps the two records aligned.

Repositories and reporting

Serialisation data flows up through a layered architecture. A site-level system controls the line, holds the number ranges and records commissioning events. That reports to an enterprise repository holding all data for the brand owner across sites and contract packers. The enterprise layer reports outwards to the destination scheme, whether a national verification system or a trading partner under a bilateral exchange.

For a contract packer that means integration work. Every customer brings a different platform, and each connection must be specified, tested and qualified before the first commercial batch.

Why serialisation matters

The founding driver was falsified medicines. A unique, verifiable identifier makes it far harder to introduce counterfeit product into a legitimate distribution chain, because a duplicate or unknown serial fails verification at the point of dispense.

The secondary benefits have proved at least as valuable. Recall precision improves sharply when a manufacturer can identify which packs went to which customer, rather than withdrawing a whole batch. Diversion and grey market activity become visible when packs meant for one market are scanned in another. Reimbursement fraud is harder when a pack can only be claimed once.

The global patchwork

There is no single global standard, only schemes built on common GS1 foundations with different rules on top.

EU FMD. A unique identifier in a 2D DataMatrix plus an anti-tampering device on the outer packaging. Data is uploaded to the European Medicines Verification System, and packs are decommissioned at the point of dispense. The anti-tamper device is a physical requirement, not a data one, applied and inspected on the line.

US DSCSA. The four-identifier DataMatrix described above. The stabilisation period ran to 27 May 2026, and from 28 May 2026 aggregation and interoperable EPCIS 1.2 or later exchange became enforceable, so every case reports the unit serials it contains and every pallet the case serials.

Other national schemes. Several markets run their own systems with their own coding and reporting rules, often requiring in-country product registration and direct upload to a government platform. A pack compliant in one market is not automatically compliant in another.

The UK position, and why it makes serialisation an export capability

This is the point most commonly got wrong. EU FMD safety features ceased to apply in Great Britain on 1 January 2021. Under the Windsor Framework they also ceased to apply in Northern Ireland from 1 January 2025: EU-compliant 2D codes and serial numbers must be removed or covered for the NI market, the UK repository is no longer accessible, and anti-tamper devices are encouraged but not mandatory for FMD purposes. The MHRA is now sole regulator for the whole UK.

There is therefore no mandatory medicines serialisation scheme for the UK domestic market. What does apply is "UK Only" labelling at a minimum of 7 point, which may appear anywhere on the outer packaging, and the rule that from 1 January 2025 joint EU/UK packs are not permitted, so a UK-specific outer carton is required.

The commercial consequence is straightforward. For a UK packer, pharmaceutical serialisation is not a domestic compliance chore. It is an export enabler. A site that can serialise, apply anti-tamper devices, aggregate and manage rework data can supply the EU, the US and other regulated markets from the UK. A site that cannot is limited to unserialised destinations.

Key takeaways

• Pharmaceutical serialisation assigns a unique identifier to each saleable pack, carried in a GS1 2D DataMatrix using structured application identifiers.
• Inline vision verification decodes the printed code and grades it under ISO 15415, with grade B or better the common expectation.
• Serial numbers must be reconciled as rigorously as printed components, and rework is the most frequent source of data breaks.
• There is no mandatory UK domestic serialisation scheme, since FMD safety features ceased to apply in Great Britain in 2021 and Northern Ireland in 2025.
• Serialisation is therefore an export capability, enabling supply into EU FMD, US DSCSA and other national schemes.

Talk to Central Pharma about US-bound packing

Central Pharma has been a contract filler and packer to the pharmaceutical, medical device, cell and gene therapy and healthcare sectors since 2006, from a 267,000 sq ft licensed site in Bedford. Serialisation is run by dedicated in-house specialists covering global directives, with anti-tamper device application, full aggregation and reworking data management. The site holds an MHRA MIA and WDA(H), is FDA registered for secondary packing and labelling, and QP releases to more than 60 countries. To discuss a serialised packing project, get in touch.

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