What is WLTP?

The Worldwide Harmonised Light Vehicle Test Procedure (WLTP) is a new global regulation (test) for measuring the level of air pollutants, CO2 emissions and energy consumption in light duty vehicles – cars and vans. It replaces the outdated New European Driving Cycle (NEDC) test that has been used for over 20 years. WLTP embraces an improved range of dynamic and robust testing procedures, and better reflects real-world driving conditions for all vehicle powertrains. These improvements produce much more accurate and realistic results, giving the consumer more confidence in fuel economy, CO2 emissions and electric range values presented for a new car.

Key Policy Milestones in the Transition To WLTP

Manufacturer type approval for new cars

· WLTP has been mandatory for new car models approved from 1 September 2017 and will be mandatory, with exceptions, for all new car registrations from 1 September 2018.


· From 1 September 2017 cars approved under WLTP will continue to be taxed against NEDC CO2 emission figures.

· From 6 April 2020 taxation will adopt the WLTP CO2 emission figure.

Consumer Information

· From 1 September 2017 consumer information, covering car labels and displays at dealer showrooms plus manufacturers’ printed marketing material, will show NEDC CO2 and fuel consumption figures for cars approved under WLTP.

· During 2018 manufacturers will start showing WLTP performance data for new car models on their websites; this data will also be shown on the VCA website.

· From January 2019 consumer information will switch to presenting WLTP fuel and electricity consumption plus electric range figures. The NEDC CO2 value will continue to be presented in consumer information; the WLTP CO2 value will not be shown.

· From 6 April 2020 consumer information will switch to showing the WLTP CO2 emission figure.

· The Vehicle Certification Agency (VCA) will be releasing guidance on presenting WLTP values in consumer information over the next few months. The VCA will start showing WLTP values on the Government’s fuel economy and CO2 database from September 2018.

What new data will we see for WLTP tested cars?

Old NEDC test:

  • 2.5 miles urban
  • 4.3 miles extra urban
  • 6.8 miles combined: A mixed journey average of both of the elements in the test.
  • 1.9 miles Low Speed (city driving): City Centre journey with maximum 35 mph.
  • 3.0 miles Medium Speed (Town Driving) Town or suburban driving, maximum 50 mph.
  • 4.5 miles High Speed (Rural Driving): Rural driving, A-road or dual carriageway journey, maximum 60 mph.
  • 5.1 miles Extra High Speed (Motorway): Motorway driving with maximum speed of 81 mph, typical of a European motorway.
  • 14.5 miles Combined: A mixed journey average of all the elements.

New WLTP test:

Recommendations for consumer information

  • While consumers should receive WLTP fuel consumption and electric range data as early as possible, it is essential that they are not confused by the existence of both NEDC and WLTP data.
  • WLTP data should be shown separately to NEDC on manufacturers’ websites, car buying websites and print media. A person could mistakenly think a car tested under WLTP was less efficient and so more expensive to run than a similar car tested under NEDC.
  • It should be made clear that the NEDC CO2 emission value is used for taxation. Consumers should be informed of any changes in taxation (VED/BIK), as a result of the switch to the WLTP CO2 figure, well in advance of April 2020.
  • Comparison tools and filters, plus tax and fuel calculators, on car buying websites should appropriately use NEDC and WLTP fuel consumption and CO2 emission figures; taking into consideration both new and used cars. Motoring websites that list cars in categories such as ‘best MPG’, ‘most economical’, ‘lowest CO2 ’, ‘best city cars’, should ensure that data used as the basis of these ratings is not a combination of NEDC and WLTP data. Like for like comparisons should be adopted. Consideration should be given to regulatory switch dates for taxation and consumer information.
  • Consumers should be made aware of the impact of optional equipment fitted by the manufacturer on CO2 and fuel consumption figures as well as electric range. Presenting a range of values for a particular car model could assist with communicating this in consumer information. This could, for example, show a car model’s base CO2 emissions (lowest value) and then with all optional equipment fitted (high value).
  • It should be made clear to consumers which ‘official’ test procedure the figures presented for CO2, fuel and electricity consumption and electric range are based upon. This will avoid confusion and misinterpretation when comparing different car models.
  • Consumers should be presented with fuel consumption and electric energy consumption figures for plug-in hybrid cars, in conjunction with electric range figures. This will help the consumer understand how plug-in hybrids perform under different journey patterns and enable comparison with other technologies.

Find more information on: https://www.lowcvp.org.uk/wltp or email louise.woods@rmif.co.uk to receive the full document.