Article By Ben Custard
Car exhaust

GUIDE: What Are WLTP And RDE Vehicle Emissions Standards?​

Soon, all new cars and vans will be subjected to a much tougher emissions test. As a result, a car’s quoted MPG and CO2 figures are set to be a lot lower, but you’re more likely to be able to reach these figures.

What Is WLTP?

WLTP, or Worldwide Harmonised Light Vehicle Test Procedure (should that be WHLVTP?), comes into force next month, providing a shake-up to current economy and efficiency benchmarks. Cars have long been tested and taxed on their emissions, and the new WLTP cycle replaces the NEDC (New European Driving Cycle) test.

However, WLTP emissions tests are far more thorough and stringent. NEDC tests produced completely unrealistic figures that were impossible to replicate in real life. In tests, cars were run at a set speed without having to stop and start, and any acceleration and braking happened at a snail’s pace. Some manufacturers even set their cars up to know when they were being put through these tests, to cheat the system and produce outstanding figures.

Ford Edge ST-Line rear
Ford Mustang EcoBoost exhausts

When Is The Change Happening?

This change comes into effect in September 2018, as vehicle emissions levels are becoming dangerously high in some places. WLTP is designed to more accurate to real situations, thanks to a more varied test cycle. A new part of the test features a real driving emissions (RDE) segment, which is taken on real roads. It’s likely that there will still be a difference in the two figures, but by 2021 the margin will be much tighter.

Renault Megane RS exhaust

Will Car Tax Increase With WLTP And RDE?

Car tax could increase with the full introduction of these new emissions tests. Some manufacturers have reported that their CO2 figures are up to 15% higher under WLTP compared to NEDC cycles, so the same car could cost you a bit extra in tax come September.

However, buy a car before the end of August and you won’t have to pay a different tax figure, so that could be an incentive if you’re not sure about waiting for the new 68-plate registration.

If you're confused about any aspect of new car buying, tweet us @Hartwell_co_uk and we'll guide you through it!

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