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Unique Device Identification
System for adequate identification of medical devices through distribution and use.
Reviewed by Christian Espinosa, Founder, Blue Goat CyberLast reviewed September 19, 2026
Definition
Unique Device Identification (UDI) is a system that uses an alphanumeric code to uniquely identify a medical device through its distribution and use. It comprises a Device Identifier (DI) and a Production Identifier (PI), and is registered in the GUDID (US) or EUDAMED (EU). The DI identifies the labeler and the specific version or model, while the PI can carry lot, serial number, expiry and manufacture date. The code must appear on labels in both plain text and automatic identification and data capture (AIDC) form, such as a barcode. What the regulation says
In the US, FDA's UDI final rule, published on September 24, 2013 and effective December 23, 2013, established requirements in 21 CFR parts 801 and 830. Sections 801.20 and 801.40 require covered devices to bear a UDI on labels and packages in plain text and automatic identification and data capture (AIDC) form, subject to exceptions. Section 801.45 requires direct marking for devices intended for repeated use and reprocessing before each use, subject to exceptions. Labelers submit device identification data to GUDID under section 830.300. GUDID does not store production identifiers such as individual lot or serial numbers.
Regulation (EU) 2017/745, adopted on April 5, 2017 and generally applicable from May 26, 2021, establishes the EU framework through Article 27 and Annex VI. Manufacturers assign UDIs and provide required device data to EUDAMED, with implementation subject to applicable transition provisions. UDI carrier requirements have phased application dates by device class, with later deadlines for direct marking of reusable devices. The EU also uses a Basic UDI-DI to link related devices and regulatory documentation; it is distinct from the UDI displayed on labels. These requirements support MedTech traceability, recalls and post-market surveillance.What this means in practice
UDI supports recall management, adverse event reporting, and supply chain traceability. It is mandatory in the U.S., EU, and an increasing number of jurisdictions. The Device Identifier (DI) is the fixed portion that identifies the labeler and specific version or model. The Production Identifier (PI) is a conditional, variable portion that may include lot or batch number, serial number, expiration date, manufacturing date, and (for HCT/Ps) the distinct identification code.Examples
- A pacemaker labeled with a GS1-issued UDI containing a GTIN as the DI and lot number plus expiration date as the PI.
- An implantable orthopedic screw carrying a direct-part-marked UDI so it remains identifiable after unpacking.
Use cases
1 scenario1
EU MDR labeling refresh across 200 SKUs
Labeling specialistThe team assigns UDI-DI/UDI-PI to every SKU using a GS1 issuing agency, prints AIDC and HRI on labels, and uploads device data to EUDAMED. Production scanners verify each label before release.
OutcomeDevices ship into the EU on time; hospitals can scan UDIs into their inventory and adverse event reports.
Common pitfalls
- •Confusing UDI-DI with UDI-PI. Regulators, GUDID, and EUDAMED all expect both to be handled correctly on labels and in submissions.
- •Assuming a single UDI covers every package level. Each package configuration (unit, box, case) needs its own DI.
- •Not updating GUDID or EUDAMED when labeling, sterilization method, or configuration changes.
- •Treating UDI as a labeling-only task. It touches PLM, ERP, regulatory, and post-market systems.
Frequently asked questions
UDI-DI (Device Identifier) is the fixed identifier for a specific device version or model and its packaging level. UDI-PI (Production Identifier) is the variable portion that identifies the specific production unit, typically including lot or batch number, serial number, expiration date, or manufacturing date.
Cross-references
Related terms
Grouped by themeEditor's picks
· Hand-selected related conceptsRegulatory
EUDAMED
European Database on Medical Devices.
Regulatory
EU Medical Device Regulation(MDR)
Regulation (EU) 2017/745 governing medical devices in the European Union.
Post-Market
Global Unique Device Identification Database(GUDID)
FDA database holding key device identification information for all UDIs.
Post-Market
Post-Market Surveillance(PMS)
Activities to monitor device safety and performance after market release.
EU MDR Essentials
· From this learning pathRegulatory
CE Mark
Mandatory European conformity mark for medical devices placed on the EU market.
Regulatory
EU In Vitro Diagnostic Regulation(IVDR)
Regulation (EU) 2017/746 governing in vitro diagnostic medical devices in the EU.
Regulatory
Notified Body(NB)
EU-designated organization that assesses conformity of medical devices under MDR and IVDR.
Post-Market
Periodic Safety Update Report(PSUR)
Periodic EU MDR/IVDR report summarizing post-market surveillance findings.
Adjacent lesson
Cited by
Where this term appears across MedTech Terms.
Learning paths (1)
- EU MDR EssentialsLesson 6 of 9
Ecosystems (2)
Latest in MedTech
Sources
3 sourcesEvery citation below opens the original document. Each is graded against our source-tier hierarchy so you can see what rests on binding law versus commentary.
Tier 2Regulator guidance and consensus· 3
Link health: 2 verified 1 unchecked· last checked 2026-06-20
FDA·1NIH / FDA·1European Commission·1
- 1UDI System (FDA)Tier 2 VerifiedFDAfda.gov
- 2AccessGUDIDTier 2 UncheckedNIH / FDAaccessgudid.nlm.nih.gov
- 3EU UDI (MDR)Tier 2 VerifiedEuropean Commissionhealth.ec.europa.eu
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