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Euro 6 emissions regulations – the facts

  • What is Euro 6?
  • We take a look at how Euro 6 legislation is changing
  • Find out how it could affect you when buying your next car

Euro 6 is a vehicle emissions standard that all new cars sold in Europe must meet. It became mandatory in September 2015.

What does Euro 6 mean?

The Euro emissions standards have been in place since 1993 and, since September 2015, it has been mandatory for every newly registered vehicle to meet the Euro 6 vehicle emission standard.

Designed to tackle the issue of air pollution, the Euro vehicle emission standards have become slowly more stringent, pushing manufacturers to produce ever more efficient and environmentally friendly cars.

They cap the levels of harmful exhaust emissions that a car produces on the road, and these limits are meticulously scrutinised before a new car is released onto the market.

The Euro 6 emission standard also sets a legal requirement for a car manufacturer to average CO2 emissions below 130g/km across its entire range – this will be reduced to 98g/km in 2020.

But, what’s most obvious about the Euro 6 standard is the focus on restricting diesel NOx emissions. It seems likely that owners of older diesel cars will continue to be targeted by increasingly rigorous penalties.

Here are the standards for petrol engines as set by Euro 6:

  • Carbon monoxide - 1.0g/km
  • Total hydrocarbon emissions: 0.10g/km
  • Non-methane hydrocarbon emissions: 0.068g/km
  • Nitrogen oxides: 0.06g/km
  • Particulate matter: 0.005g/km (direct injection only)

These are the diesel standards set by Euro 6:

  • Carbon monoxide: 0.50g/km
  • Hydrocarbons and Nitrogen oxides: 0.17g/km
  • Nitrogen oxides: 0.08g/km
  • Particulate matter: 0.005g/km

How does Euro 6 affect me?

Driving a Euro 6 compliant car will first and foremost exempt you from paying the new Ultra Low Emission Zone (ULEZ) charge introduced in April 2019 – although, while this is a requirement of diesel engines, petrol engines compliant to Euro 4 or later will also be exempt.

You can be sure that a car with a Euro 6 certificate will be cheaper to tax too thanks to lower CO2 emissions contributing to lower VED tax bands, while newer engine is also likely to be much more efficient than an older model, resulting in much lower residual costs.

Use our Car Tax Calculator to find out exactly how much road tax you will pay on your car.

Should I buy a new Euro 6 compliant car?

If protecting the environment and saving money while you do it appeals to you, then yes. Be wary of buying from new however, as you can expect manufacturers will be trying to recoup some of the substantial investment necessitated by the introduction of Euro 6 – this does seem to depend on the dealer, though.

There is no legal requirement for you to do so though, so you refuse to turn away from your noisy, CO2 belching V8 then you don’t have to worry as, for now at least, there is restriction on their use other than some hefty running costs.

What about the RDE standard?

Current Euro 6 emissions tests are undertaken in laboratory conditions, so Real Driving Emissions (RDE) tests have been introduced to try and ensure the emissions figures advertised by manufacturers are attained in a range of real-life driving conditions. 

Current Euro 6 emissions tests are undertaken in laboratory conditions,

All newly registered cars will be subject to RDE1 tests from the start of September 2019, which will factor in a margin of 2.1 times the NOx limit imposed by Euro 6. Cars that pass an RDE1 will be certified as Euro 6d-temp.

As of the beginning of 2021, the margin on NOx emissions will be tightened in the new RDE2 tests, and all complicit new cars will be certified as Euro 6d.

It should be noted that any diesel cars that fail to meet the RDE standard will be listed one VED band higher for first year tax than was originally indicated by the Euro 6 test.

The Euro standard of a new car has been indicated on the V5c vehicle registration document since September 2018.

What is Euro 6.2 and does it avoid the diesel surcharge?

Emissions standards are planned well in advance, as is legislation to respond to them. Euro 6.2 - applicable to newly launched cars from September 2017 and all new registrations from September 2018 - is also known as Euro 6d-TEMP. It is a step in the process linking Euro 6 targets to real-world emissions testing.

The Finance Act 2018 clear on how the diesel surcharge for VED and BIK will be applied. however, and regardless of actual emissions the work undertaken by manufacturers to meet Euro 6d ahead of the 2020-2021 deadline is essentually overlooked.

'A vehicle meets the Euro 6d emissions standard only if it is first registered on the basis of an EU certificate of conformity which indicates that the exhaust emission level is Euro 6d (and it does not meet that standard if it is first registered on the basis of an EU certificate of conformity which indicates that that level is Euro 6d-TEMP).'

Euro 6.2 compliance has little relevance to the UK car buyer beyond the knowledge that their car is being tested against real-world emissions and conforms to mandatory standards across Europe - some other countries recognise the new standard for emissions.

In some European cities, Euro 6d-TEMP is used to determine if a vehicle is sufficiently clean to enter environmental zones such as polluted city centres - and if you plan on driving in Germany, you may need a blue badge indicating type approval for the lower emissions.

You can obtain the required windscreen sticker here.

Whether or not they meet the reduced NOx and CO2 benchmarks that define the target HMRC considers low enough to avoid the diesel supplement, as the cars will not be certified under Euro 6d, they'll still attract the charges.

CO2 emissions and climate change

In an effort to mitigate the effects of greenhouse gases, the Climate Change Act (2008) requires the UK to reduce greenhouse gas emissions by at least 34% by 2020 and 80% by 2050 compared with 1990 levels - with transport playing a critical role in meeting these targets.

The accumulation of these gases (most importantly CO2 and methane) in the atmosphere is a key contributor to climate change.

These harmful gases in the air have steadily increased and the effect they have on climate change is beginning to become much more obvious with heatwaves, floods, droughts and storms becoming more frequent around the world. Let us also not forget the associated health risks with the rise in these harmful gases.

Petrol vs diesel - the great debate

Should you buy a petrol or a diesel car? This debate continues to rage on; find all the latest information about petrol vs diesel cars here.

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Looking for more jargon-busting motoring meanings? Head over to our Parkers Car Glossary page and take a look at our other definitions