MDR Classification Rules

Updated July 2026

MDR classification rules are the criteria used to determine the risk class of a medical device under Regulation (EU) 2017/745 on medical devices.

This guide explains, for informational purposes, what classification rules are, where they are defined and how they are organised in Annex VIII of the MDR.

Sheet with the title MDR Classification Rules and reference to Regulation (EU) 2017/745

In this guide

What are MDR classification rules and how are they applied?
Where are MDR classification rules defined?
How are the rules in Annex VIII organised?
Non-invasive devices
Invasive devices
Active devices
Special rules
Classification rules and notified bodies
Why this guide does not reproduce all the rules in Annex VIII
Why this guide does not classify devices

What are MDR classification rules and how are they applied?

MDR classification rules are used to place a medical device in one of the risk classes provided for by the Regulation.

The MDR provides for four risk classes:

class I;
class IIa;
class IIb;
class III.

The application of the classification rules is based on the intended purpose of the device.

Classification also depends on elements such as the associated risks, duration of use, degree of invasiveness, the part of the body concerned, the composition of the device and the specific characteristics of the product.

Annex VIII provides that, if several rules or, within the same rule, several sub-rules apply to the same device based on its intended purpose, the strictest rule and sub-rule resulting in the higher classification apply.

In general terms, the higher the risk class, the greater the level of control required in the conformity assessment process.

Where are MDR classification rules defined?

The classification rules are defined in Annex VIII of Regulation (EU) 2017/745.

Article 51 of the MDR states that devices are divided into classes I, IIa, IIb and III, taking into account the intended purpose of the devices and their inherent risks. Classification is carried out in accordance with Annex VIII.

An important document for understanding this topic is MDCG 2021-24 rev.1 — Guidance on classification of medical devices.

The European Commission also makes available the Manual on borderline and classification under Regulations (EU) 2017/745 and 2017/746, which collects guidance on borderline cases and classification topics.

How are the rules in Annex VIII organised?

Annex VIII of the MDR contains 22 classification rules, organised into main groups.

In simplified terms, the rules are divided as follows:

rules 1 to 4: non-invasive devices;
rules 5 to 8: invasive devices;
rules 9 to 13: active devices;
rules 14 to 22: special rules.

This structure helps understand the types of elements considered by the Regulation, without replacing the reading of the official text of Annex VIII.

Non-invasive devices

In general terms, these are devices that do not penetrate inside the body, either through a body orifice or through the surface of the body.

This category may include, for example, devices that come into contact with the skin, devices intended for channelling or storing substances, or devices intended to come into contact with blood, body liquids, cells or tissues outside the body.

The classification of these devices depends on the characteristics of the device, its intended purpose and the type of interaction expected with the body or with substances intended to be introduced into the body.

Invasive devices

According to the MDR, an invasive device is a device that penetrates partially or entirely inside the body, either through a body orifice or through the surface of the body.

Under the MDR, the classification of invasive devices takes into account various elements, including duration of use, type of invasiveness, the part of the body concerned and the level of risk associated with the intended purpose.

Implantable devices may also be relevant in this context. In general terms, an implantable device is a device intended to be totally introduced into the human body or to replace an epithelial surface or the surface of the eye by clinical intervention, and to remain in place after the procedure.

This category covers very different situations, which is why the main reference remains Annex VIII of the Regulation.

Active devices

According to the MDR, an active device is a device whose operation depends on a source of energy other than that generated by the human body for that purpose or by gravity, and which acts by changing or converting that energy.

Active devices may include, for example, devices intended for therapy, diagnosis, monitoring or support of physiological functions, depending on the intended purpose and characteristics of the product.

The classification of active devices depends on the role of the device, the type of energy used or administered, the information provided and the potential risks associated with its use.

Special rules

Rules 14 to 22 are special rules applicable to particular types of devices or situations.

This category may include, for example, devices incorporating a substance which, if used separately, may be considered a medicinal product, devices manufactured using tissues or cells of human or animal origin or their derivatives, devices used for contraception and other specific categories provided for in Annex VIII.

These rules concern categories that require particular attention due to their composition, function, mode of use or interaction with the human body.

The special rules are an integral part of the MDR classification system and may affect the final class of the device when the conditions provided for by the Regulation are met.

Classification rules and notified bodies

Device classification is connected to the conformity assessment pathway and, in many cases, to the involvement of a notified body.

In general, devices belonging to higher risk classes require greater involvement of the notified body. The MDR generally provides for a different level of involvement depending on the class of the device and the applicable conformity assessment procedure.

Some class I devices may require the involvement of a notified body only for specific aspects, for example in the case of sterile devices, devices with a measuring function or reusable surgical instruments, as provided for by the Regulation.

For this reason, classification is a relevant element in the regulatory framework of the device, but this guide does not determine the class applicable to specific cases.

Why this guide does not reproduce all the rules in Annex VIII

This guide does not reproduce the full text of the MDR classification rules because the official reference remains Annex VIII of Regulation (EU) 2017/745.

MDCG 2021-24 rev.1 provides useful guidance for understanding the classification system for medical devices.

Reproducing all the rules on this page would increase the risk of duplicating the official text or oversimplifying provisions that need to be read in their full context.

For this reason, this guide only explains the general structure of the rules and refers to the official sources.

Why this guide does not classify devices

This guide does not determine the risk class of specific devices.

Classification depends on elements such as the intended purpose, intended operation, duration of use, invasiveness, the part of the body concerned, the composition of the device, the technologies involved and the applicable regulatory context.

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

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