Updated July 2026
MDR codes are a tool used to describe the scope of designation of notified bodies under Regulation (EU) 2017/745 on medical devices.
This guide explains, for informational purposes, what they are, where they are defined and why they are relevant in the context of notified bodies.
MDR codes should not be confused with device classification: the risk classes under the MDR are I, IIa, IIb and III, while the codes relate to the technical areas and competences covered by the designation of a notified body.
In this guide
- What are MDR codes?
- What are MDR codes used for?
- Where are MDR codes defined?
- Types of MDR codes
- MDA and MDN codes
- MDS codes
- MDT codes
- MDR codes and notified bodies
- Conditions and limitations in the scope of designation
- Why this guide does not provide a complete table of MDR codes
- Why this guide does not assign codes to devices
What are MDR codes?
MDR codes describe types of devices, specific characteristics, technologies or processes that are relevant in the context of notified body designation.
Commission Implementing Regulation (EU) 2017/2185 establishes the list of codes and corresponding types of devices used to specify the scope of designation of notified bodies in the medical device sector under Regulation (EU) 2017/745.
In other words, they help specify the technical areas covered by the designation and the competences relevant for certain conformity assessment activities.
What are MDR codes used for?
MDR codes are mainly used by designating authorities to define the scope of designation of notified bodies.
MDCG 2019-14 also explains that they may be used by notified bodies to describe staff qualifications and the competences required to assess certain types of devices.
In the context of conformity assessment, the codes may therefore be relevant to describe:
- the scope of designation of a notified body;
- the qualifications of the personnel involved;
- the competences required for specific types of devices;
- the allocation of resources in assessment activities.
Where are MDR codes defined?
MDR codes are defined in Commission Implementing Regulation (EU) 2017/2185, which contains the lists used to specify the scope of designation of notified bodies.
An important document for interpreting them is MDCG 2019-14 — Explanatory note on MDR codes.
MDCG 2019-14 explains the different levels of codes and their use, including in relation to the allocation of resources in conformity assessment activities. The document also clarifies that MDCG guidance documents are not legally binding and that only the Court of Justice of the European Union can provide binding interpretations of Union law.
Types of MDR codes
MDR codes are organised into different categories. The main ones are:
- MDA codes;
- MDN codes;
- MDS codes;
- MDT codes.
These categories do not all have the same function. Some describe the type of device, while others refer to specific characteristics, processes or relevant technologies.
MDA and MDN codes
MDA and MDN codes reflect the design and intended purpose of the device.
MDCG 2019-14 indicates that MDA and MDN codes are considered according to a hierarchical logic and that, for each device, only one MDA or MDN code is selected.
In general terms:
- MDA codes relate to active devices;
- MDN codes relate to non-active devices.
These codes are particularly relevant for describing the type of device and for the allocation of personnel involved in technical documentation review or in audits relating to product aspects.
MDS codes
MDS codes are horizontal codes and describe specific characteristics of the device.
Unlike MDA and MDN codes, multiple MDS codes may be applicable to the same device. MDCG 2019-14 indicates that from zero to several MDS codes may be assigned to a device, depending on the applicable characteristics.
They may relate, for example, to particular characteristics that require specific competences for the assessment.
MDT codes
MDT codes describe technologies or processes used in the manufacture and making available of devices.
MDCG 2019-14 links these codes in particular to the allocation of personnel involved in audits, for example when competences relating to specific manufacturing processes are required.
In this case as well, multiple MDT codes may be relevant for the same device, depending on the technologies and processes considered.
MDR codes and notified bodies
MDR codes are closely connected to the scope of designation of notified bodies.
When consulting the designation of a notified body, the codes may indicate the technical areas, types of devices, characteristics or activities for which the body is designated.
For this reason, MDR codes are connected to the topic of notified bodies, but they do not replace the official information provided in applicable sources, such as NANDO and designation documents.
Conditions and limitations in the scope of designation
The scope of designation of a notified body may include conditions or limitations associated with certain codes.
MDCG 2019-14 explains that conditions, including any limitations, should be formulated in an unambiguous way and should relate to characteristics of the device.
These conditions help clarify the actual scope of the designation and may indicate inclusions or exclusions relating to specific types of devices or technical characteristics.
Why this guide does not provide a complete table of MDR codes
This guide does not provide a complete table of MDR codes.
This choice is intentional: the complete list of codes is available in Commission Implementing Regulation (EU) 2017/2185, while MDCG 2019-14 provides explanatory guidance on their use.
Official sources remain the main reference for consulting the codes, the corresponding types of devices and the applicable indications.
For this reason, this guide only explains the MDR code system and refers back to the official sources.
Why this guide does not assign codes to devices
The association between codes and devices depends on elements such as the characteristics of the device, its intended purpose, the technologies involved, the manufacturing processes and the context of the conformity assessment procedure.
For this reason, this page is descriptive in nature and refers to the official texts and reference documents.
Informational note
This guide is published for informational purposes only and does not constitute regulatory, legal, technical or professional advice.
The information is based on publicly available sources and was verified as of the date of publication or the latest update of this page. It may therefore not reflect subsequent changes or developments.
For assessments relating to specific cases, reference should be made to the official texts, the latest documentation issued by the competent authorities and, where appropriate, qualified professionals.
Official sources
- Regulation (EU) 2017/745 on medical devices
- Commission Implementing Regulation (EU) 2017/2185
- MDCG 2019-14 — Explanatory note on MDR codes
- NANDO — New Approach Notified and Designated Organisations
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Related resources
- What is the MDR?
- MDR Notified Bodies
- MDR Classification Rules
- MDR Harmonised Standards
- MDR Post-Market Surveillance
- UDI and Basic UDI-DI
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© Simone Ronco. Unless otherwise stated, the editorial content of this guide is an original work.
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