The Worldwide Harmonised Light Vehicle Test Procedure. What the changes mean for you and your busines

People working together

    What is WLTP and what does it mean for you?

    Under conditions defined by EU law, the WLTP laboratory test is used to measure fuel consumption and CO2 emissions.

    WLTP is the vehicle testing cycle that aims to improve the accuracy of vehicle emissions
    and fuel consumption figures provided by OEMs (Original Equipment Manufacturers). It replaces the outgoing NEDC (New European Driving Cycle) which has been in force since the 1990s and no
    longer accurately reflects modern vehicle emissions or driving.


    The changes at-a-glance

    • More realistic driving behaviour
    • A wider range of driving situations (urban, suburban, main road, motorway)
    • Longer test distances
    • More realistic ambient temperatures, closer to the European average
    • Higher average and maximum speeds and drive power
    • More dynamic and representative accelerations and decelerations
    • Shorter stops
    • Optional equipment: CO2 values and fuel consumption are provided for individual vehicles as built
    • Stricter car set-up and measurement conditions
    • Enables best and worst-case values on consumer information, reflecting the options available for similar car models
    EV Close up loading cable

    What are the differences between WLTP and NEDC?

    The new WLTP procedures seek to replicate real world driving and align emissions to individual vehicles more accurately.
    Testing time increases to 30 minutes with four driving phases instead of two. Speed, gear changes and distance travelled are all increased, whilst CO2 figures are tested at lower temperatures to portray a more realistic picture of a car’s emissions cycle.
    WLTP tests recognise that some optional extras have an effect upon aerodynamics, weight and rolling resistance and will adjust CO2 and MPG values accordingly. Under the previous testing structure, optional equipment (larger alloy wheels, body styling, heated seats etc.) was not considered.

    How does the new lab test compare?


    • Duration: 20 minutes
    • Distance: 6.8 miles
    • Speeds: 21mph average - 75mph maximum
    • Gear shift points: Fixed
    • Test temperature:20-30 degrees


    • Duration: 30 minutes
    • Distance: 14.4 miles
    • Speeds: 28.9mph average - 81.3mph maximum
    • Gear shift points: Different (depending on vehicle)
    • Test temperature:14-23 degrees

    Test Cycle

    Moving from a single test cycle, WLTP will introduce 3 different test cycles depending on the power-to-weight class of the vehicles. The appropriate cycle will then be used for the specific vehicle

    Road Type

    Going from 2 phases with NEDC, the new WLTP test will have 4 phases to represent: urban city, suburban, A road, and motorway

    Influence of optional equipment

    CO2 values will now take into account the weight and effects on aerodynamics of optional equipment such as air conditioning, tyres etc

    CO2 and fuel consumption

    Consumption measurements will now be closer to what drivers experience
    on the road

    Benefits of real world emissions testing
    The Real-world emissions test is supplementary to WLTP, taking take into consideration:

    • Road Type
    • Weather
    • Conditions
    • Traffic
    • Conditions
    • Road Gradient
    Man pulling suit case

    What does the change look like over time?


    SEPTEMBER every new car tested under WLTP.
    DECEMBER government releases Review of WLTP and Vehicles Taxes consultation. Some manufacturers announced that their vehicles are RDE2 compliant.


    JULY WLTP consultation response.

    • 2% reduction in CCT for new cars
    • Post April 2020 Freeze for existing cars
    • Zero tax on electric cars

    SEPTEMBER WLTP figures used for all vans.


    JANUARY new car models must be RDE2 compliant to go on sale.
    APRIL WLTP CO2 to be used for company car tax purposes & VED. New dynamic interfaces applied to get impact of options on CO2 and MPG. Corporation tax falls to 17%.


    JANUARY all cars on sale to be RDE2 compliant. Ultra low emitting vehicle (ULEV) reclassified to 50g/km from 75g/km.

    POST 2021 van VED based on CO2 emissions.

    Fast forward

    Do you like to read more, are you curious about our related solutions and cases, or would you like to find out what Athlon can do for you?