ECE R48 - installation of vehicle lighting

UNECE Regulation No. 48, commonly referred to as ECE R48, sets requirements for the installation of vehicle lighting, including the position, number, visibility and operation of lamps. The regulation is widely used in vehicle type approval across Europe and is also relevant to vehicles placed on the market or used in the UK, depending on the applicable approval framework.

This regulation applies to vehicles in categories M, N and O. In practice, this includes passenger cars, trucks, trailers and trailers. For manufacturers, bodybuilders and fitters, ECE R48 is therefore an important guideline for mounting, surface mounting and testing.

Are you looking for clarity on the regulations governing vehicle lighting on trucks, semi-trailers or trailers? If so, ECE R48 is one of the most important regulations to understand. In this article, you can read what the regulation entails, which vehicles it applies to and how ECE R48 relates to other ECE regulations such as R148 and R149.

UNECE R48: installation of vehicle lighting

ECE R48 regulates the installation of lighting and light-signalling devices on vehicles. The regulation determines which lighting must be present, where it is mounted and which visibility requirements the installation must meet.

In practice, ECE R48 is particularly relevant to the surface mounting, mounting and testing of vehicles in categories M, N and O. These include passenger cars, trucks, trailers and trailers.

ECE R48 looks at, among other things:

• application per vehicle category
• placement of lighting
• mounting height and position
• symmetrical mounting
• visibility angles

Important requirements within ECE R48

ECE R48 sets requirements for how lighting is used and mounted on a vehicle. In doing so, the regulation looks not only at the presence of lighting, but also at its position, visibility and correct operation.

• Requirements by vehicle function and vehicle category: ECE R48 specifies, for each light function, whether lighting is mandatory, optional or prohibited. For example, main-beam headlamps are mandatory on motor vehicles and prohibited on trailers, whilst triangular red retroreflectors are, in fact, mandatory on trailers.
• Placement on the vehicle: The regulation sets requirements for the position in width, height and length of lighting. This involves determining how close a light function should be to the outside, front or rear of the vehicle.
• Geometric visibility: ECE R48 prescribes the angles from which lighting must be visible. This visibility differs depending on the light function. For example, fixed horizontal and vertical visibility values apply to end-outline lights.
• Symmetrical mounting: For many light functions, correct and symmetrical mounting on the left and right is essential. This is important for recognisability, correct light distribution and road safety.
• Electrical switching and correct operation: ECE R48 also sets requirements for how certain light functions switch together or influence each other. For example, separate rules apply to functions such as position lights, alarm signals and additional lighting.

When manufacturers comply with these regulations, vehicle lighting functions effectively and contributes to overall road safety. For more information on the technical requirements, please consult the official UNECE website.

Important: an approved light does not automatically comply with ECE R48. Its positioning, visibility, symmetry and correct operation on the vehicle must also meet the installation requirements.

What is the difference between ECE R48, R148 and R149?

ECE R48, R148 and R149 are often mixed up in practice, but they regulate different things. In short: ECE R48 deals with installation on the vehicle, while R148 and R149 lay down the technical requirements for the light units themselves.

Regulation	What is it all about?	Examples
ECE R48	Installation of lighting on the vehicle	Placement, height, symmetry, visibility angles
ECE R148	Technical requirements for light signalling devices	Indicators, brake lights, marker lights
ECE R149	Technical requirements for road lighting devices	Headlights, fog lights, position lights

A light may technically comply fully with R148 or R149, yet still fail inspection if the mounting does not comply with R48. Conversely, perfect installation is of no use if the light unit itself does not have the correct approval. Read more here about the difference between ECE R48 and R148.

ECE R48 for HGVs, trailers and semi-trailers

For trucks, trailers and semi-trailers, ECE R48 is particularly important for the correct mounting of vehicle lighting. The regulation not only considers the presence of lighting, but also the position, visibility and symmetry of the installation.

In practice, this is relevant for, among others:

• rear lighting
• marker lights
• contour lights
• reflectors
• additional signal lighting

A light with the correct approval may still be fitted incorrectly. In that case, the vehicle still does not meet the installation requirements of ECE R48.

For specific vehicle types and applications, you will find various in-depth articles in our knowledge base.

For example, we set out the complete regulations for truck and semi-trailer lighting in a separate guide for professionals working with trucks and semi-trailers. This includes the requirements for each vehicle category and the national exceptions within Europe. For vehicle builders who frequently work with marker lights, we provide further clarification on the regulations governing side marker lights on trucks and semi-trailers.

If you work with trailers, you may find our article on which lighting is mandatory on a trailer of interest. Alternatively, see the practical fitting instructions for trailer lighting in a separate guide. We have also set out the rules for side markings on trailers separately.

Official source: UN Regulation No. 48 - Revision 13

The current text of ECE R48 is set out in Revision 13, published by the UNECE on 3 December 2024. This is the consolidated version incorporating all amendments and supplements adopted up to that date. Vehicle builders, producers and approval authorities wishing to base their work on the applicable regulations should consult this version as their primary source.

Download: UN Regulation No. 48 - Revision 13

In addition to this consolidated version, the UNECE also publishes supplements and proposed amendments. For the latest updates and ongoing revisions, please visit the official UNECE website.

This is the official consolidated version of ECE R48 - Revision 13, published by the UNECE on 3 December 2024. This document compiles the applicable text of the regulation on the installation of lighting and light-signalling devices on vehicles.

ECE R48 requirements for trailer lighting

For trailer lighting, ECE R48 sets out requirements for the installation of lighting on Category O trailers. The regulation specifies which light functions are mandatory and sets conditions regarding positioning, visibility, symmetry and mounting height. Consequently, it is not only the light itself that is important, but above all the way in which it is fitted to the trailer. Correct installation is essential for visibility, safety and approval during inspection. You can read more about this in our guide to fitting regulations for trailer lighting. If you’d like a broader overview, do take a look at our article containing general information on trailer lighting for professionals.

Future developments within ECE R48 for trucks and trailers

Update for 2026: since 1 January 2025, new heavy trailers (categories O3 and O4) must be fitted with side lighting that operates in synchronisation with the indicators. This requirement stems from the current version of ECE R48 (Revision 13, December 2024) and will continue to be enforced during roadworthiness tests and type approval in 2026.

Please note that the points below refer to developments and directions for change within the UN Working Group GRE. These are not part of the applicable ECE R48 requirements until they have been officially adopted and come into force.

• Adaptive lighting systems: Within the development of ECE R48, attention is paid to vehicles with adaptive lighting. This includes how lighting reacts to driving situation, vehicle load and operating conditions.
• Vehicles with automated functions: Additional requirements are also considered for vehicles with driver assistance systems and automated functions. The focus here is on how lighting should function during specific vehicle movements or automatic manoeuvres.
• Monitoring of light functions and fault detection: In modern lighting systems, the importance of fault detection, system monitoring and reliable operation is continuing to grow. This is particularly relevant for vehicles that are used intensively, such as trucks and trailers.

These developments show that ECE R48 continues to adapt to new vehicle technology. For practical purposes, however, the following remains true: only officially adopted changes are part of the regulations in force.

The ‘E’ in ECE stands for Europe, but 56 countries now adhere to the ECE Regulation.

Frequently asked questions

What does ECE R48 regulate?

ECE R48 regulates the installation of lighting and light-signalling devices on vehicles. The regulation determines which lighting must be present, where it is mounted and which visibility requirements the installation must meet.

Does ECE R48 apply to trucks and trailers?

Yes, ECE R48 applies to vehicles in categories M, N and O. In practice, this also includes trucks, trailers and semi-trailers.

What is the difference between ECE R48 and ECE R148?

ECE R48 deals with the mounting and application of lighting on the vehicle. ECE R148 deals with the technical requirements of light signalling devices themselves.

How do you check that lighting is correctly fitted according to ECE R48?

Control starts with the correct light functions, followed by correct positioning, mounting height, visibility and symmetry. Only when this combination is correct does the installation comply with the principles of ECE R48.

Which version of ECE R48 is now in force?

The current version in force is UN Regulation No. 48 - Revision 13, published by the UNECE on 3 December 2024. This is the consolidated text of the regulation, including all amendments and supplements adopted up to that date. Subsequent amendments from the UN Working Group on GRE will only acquire official status after formal adoption.

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