The Measuring Instruments Directive (MID) was introduced by the EU Commission to promote free trade of measuring instruments throughout Europe and came into force on October 2006.
Approval to MID is required for meters used in any fiduciary (i.e. billing) application and for electricity meters this is MI-003 (active electrical energy meters). If meters are not going to be used for billing then installing an MID approved meter is not mandatory.
How does it affect me?
MID is applicable for loads up to 100kW. Every new meter installed for billing must be MID approved. MID makes no distinction between primary main supply meters and secondary sub-billing meters.
Currently installed meters that were approved under UK legislation prior to October 2006 may remain installed indefinitely, if they are measuring accurately. Any new meter manufactured and approved after October 2006 must be approved under the MID regulations if it is to be used for billing.
What do I need to know?
If you are a residential, commercial, industrial landlord or property manager you must employ a MID approved meter when charging for energy by meter reading (except as above).
Examples include:
- Multi-use commercial building
- Industrial Estates
- Sub-let shops or concessions
- Residential flats
- Marinas
- Caravan parks
- Data centre server supplies
- Sports facilities
What about the billing system, does the whole process need to be MID approved?
Only the meter is subject to MID. The data collection system whether it is manual reading, remote reading via data-loggers, BMS, EMS software or any other means does not need MID approval.
How to identify an MID approved meter
MID approved meters can be identified by their specific markings, as required under the Directive. These consist of the CE marking, the MID marking which is made up of the letter ‘M’ and then the year of manufacture.
(i.e. a meter manufactured in 2016 would be M16) followed by a four or three digit code representing the notified body that approved and verified the meter.

How do I find out more?
The National Measurement and Regulation Office (NMRO) aims to publish approval certificates issued by notified bodies in the UK. Certificates should also be provided by manufacturers.
Sources:
- https://www.gov.uk/guidance/mid-approved-gas-and-electricity-meters
- https://estaenergy.org.uk/groups/wp-content/uploads/sites/3/2019/01/ABB-MID-Guide.pdf