Skip advert
Advertisement

Plug-in hybrids face stricter emission tests in 2025 as misleading efficiency figures are targeted

More realistic emissions testing could see substantial tax increases for PHEV drivers

Car exhaust emitting white smoke

Plug-in hybrid cars will be subjected to more stringent emissions tests in 2025 to better represent real-world use cycles, Auto Express can confirm. It’s thought the changes could have significant implications for company car drivers, with some models expected to see big jumps in tax bands, which are based on CO2 emissions.

Advertisement - Article continues below

Existing Euro 6e emission standards will be superseded by so-called Euro 6e-bis tests, applicable to all new models launched from 1 January 2025. This will then be updated at the end of the year (31 December) to include all cars on sale, meaning existing models will have to be retested in order to comply.

Previously, the emissions tests were conducted over a simulated distance of 800km (497 miles), but Euro 6e-bis ups this to 2,200km (1,367 miles). To illustrate the effect this has on a PHEV’s emissions and fuel consumption in real world driving, the International Council on Clean Transport (ICCT) analysed the performance of a BMW X1 xDrive25e under the revised conditions. 

The ICCT said: “Over the past several years, it has become evident that the currently used UF curve does not reflect the real usage of PHEVs resulting in unrepresentatively low official CO2 emission values.

“This leads to an excessive gap between the real-world fuel consumption and the official value determined during type-approval.”

The new parameters saw the X1’s emissions rise from around 45g/km, to 96g/km. The X1 has a current Benefit-in-Kind company car tax banding of eight per cent, but the 6e-bis tests would see this number jump to 24 per cent – comparable with the most efficient pure petrol models.

A further advancement in emissions standards is expected in 2027, when ‘Euro 6e-bis-FCM’ comes into force. Under these circumstances, tested over a total distance of 4,260km (2,647 miles), the same BMW is said to emit around 122g/km.

As it stands, only cars bought brand new will be affected by the updated emissions standards; there are no plans to backdate the bandings for existing company car users. This is in contrast to the proposed introduction of VED road tax for electric car drivers due later this year, which will be applicable to both new and existing electric vehicles.

Want the latest car news in your inbox? Sign up to the free Auto Express email newsletter...

Skip advert
Advertisement
Deputy editor

Richard has been part of the team for over a decade. During this time he has covered a huge amount of news and reviews for Auto Express, as well as being the face of Carbuyer and DrivingElectric on Youtube. In his current role as deputy editor, he is now responsible for keeping our content flowing and managing our team of talented writers.

Find a car with the experts

Skip advert
Advertisement

Recommended

Hydrogen cars could soon be greener than EVs
BMW iX5 Hydrogen - front cornering

Hydrogen cars could soon be greener than EVs

If using renewable energy-based hydrogen, the ICCT says fuel cell vehicles could give off 79 per cent fewer emissions over their lifespans than ICE ca…
News
10 Jul 2025
Luxury Mercedes ‘leather’ made from old tyres is great news for the planet, and cows
‘Labfiber Biotech Leather Alternative’ - tyre and leather

Luxury Mercedes ‘leather’ made from old tyres is great news for the planet, and cows

The new material was first seen in the radical AMG GT XX concept, but will be used in the brand’s road cars
News
26 Jun 2025
BMW is killing carbon fibre to build its lightweight M cars from plants
Sustainable BMW carbon fibre replacement roof

BMW is killing carbon fibre to build its lightweight M cars from plants

Developed in collaboration a Swedish clean-tech firm, natural fibres are said to be just as strong and lightweight as carbon alternatives, plus more s…
News
19 Jun 2025
Groundbreaking Nissan solid-state EV batteries due on sale by 2028
Nissan Leaf - front cornering

Groundbreaking Nissan solid-state EV batteries due on sale by 2028

The industry is in a race to bring solid-state to the market, and Nissan isn’t too far behind the leaders
News
17 Jun 2025

Most Popular

Ford Escort Mexico gets new lease of life with MST Sports
MST Ford Escort - front 3/4

Ford Escort Mexico gets new lease of life with MST Sports

While not officially Fords, the MST Mk1 and Mk2 Sports should drive as sharply as they look
News
7 Jul 2025
New MG IM5 has the Tesla Model 3 beaten on price and range
MG IM5 - Goodwood front

New MG IM5 has the Tesla Model 3 beaten on price and range

The all-electric IM5 brings new technology and design to the MG line-up
News
10 Jul 2025
Car Deal of the Day: Hot Volkswagen Golf GTI for a cool £287 a month
Volkswagen Golf GTI - front cornering left 1

Car Deal of the Day: Hot Volkswagen Golf GTI for a cool £287 a month

The Golf GTI has been a classic from day one – and it’s our Deal of the Day for 8 July.
News
8 Jul 2025