Can I make my car ULEZ compliant?


London led the world when it unveiled the first ultra-low emissions zone – or ULEZ – which has since left lots of motorists asking, “Can I make my car ULEZ compliant?”

The answer to the question is that, yes, you can make your car ULEZ compliant but, as we will see, it's not that straightforward.

The main aim of an ultra-low emission zone, and London's started in 2019, was to improve the air that people breath in the centre of the capital.

And in October 2021, the ULEZ area was enlarged and an exemption for residents came to an end.

It is this enlargement that has led to people either selling their non-compliant cars or looking at ways of trying to meet the new regulations.

What is ULEZ?

The ultra-low emission zone is a traffic pollution charge introduced in London to improve air quality and discourage cars that produce high levels of harmful emissions. 

Instead, the ULEZ system is aimed at encouraging people to use other transport methods such as public transport, cycling or walking.

And just four months after ULEZ was unveiled, it was found that there were 13,500 fewer polluting cars heading into central London every day – compared with six months earlier.

This meant there was a 36% drop in roadside nitrogen oxide levels, which are considered to be harmful to our respiratory health.

Where was ULEZ introduced? 

ULEZ was introduced in the central London area, bounded by the North and South Circular roads.

The charge for driving a non-compliant vehicle in the zone is £12.50 per day for cars, vans and motorbikes, and £100 per day for buses, coaches and lorries.

However, drivers also face paying £15 on top for the London Congestion Charge, which applies to most cars.

That means a motorist could be facing a bill every day for entering the zone of £27.50.

What are the emission standards for ULEZ? 

To be compliant with the ULEZ emissions standards, petrol-powered cars and vans must be Euro 4 compliant. 

For diesel vehicles, they must meet the Euro 6 standard. 

This essentially means that if you drive an older, more polluting diesel or petrol car, then you will need to pay.

And if you're diesel engine complies with Euro 6 emission rules it will be exempt – as are Euro 4 petrol engines.

The age of a car will not determine whether or not they are exempt because some older cars will have compliant engines.

That's why you will need to check online whether your car is exempt or whether you need to pay ULEZ charges. You can use our ULEZ checker.

There's also a loophole for very old cars – they need to be more than 40 years old – because the owner can apply for a Ulez exemption.

This does not cover commercial vehicles, for example food trucks, but any car that was made before 1 January 1973 can apply for an exemption.

Also, military and agriculture trucks serving a specialist purpose are also exempt.

How do I make my car ULEZ compliant?

If your car is not compliant with the Ultra-Low Emission Zone standards, you will need to take action to make it compliant. 

The first step is to find out if your car is compliant – click on the link above and enter your vehicle registration number.

If your car is not ULEZ compliant and you don't fancy forking out on the charges every day, then you could consider some ways to make it compliant. 

You can look at retrofitting a non-compliant van or car to meet the requirements of the zone by either:

  • Upgrading the exhaust system
  • Changing the engine.

However, in addition to the cost of carrying out the work, you need to have the vehicle re-certified so it will be recognised by the DVSA as being compliant.

The big problem with both of these solutions is that the cost makes this process a very expensive undertaking.

If you are considering replacing the engine in your car to be ULEZ compliant, this will be a DVLA notifiable modification for the change in engine number and engine capacity.

That's because switching the engine would lead to a change in the emission values that are clearly stated in the car's V5C document or logbook.

Instead, you'll need to undertake a full rolling road emissions test to find out what the engine’s emission values are – and this is very expensive.

If you are interested in switching engines, the test must be carried out by a Vehicle Certification Agency approved test facility – it cannot be carried out at an MOT test centre.

And if you're wondering why there are not any retrofit systems available for cars, it's because they're too expensive to design and develop and then test before approval is given as a retrofit system.

Other solutions to make my car ULEZ compliant

To make your car ULEZ compliant, you could also look at emission reduction technologies, for example, selective catalytic reduction.

Though any retrofit technology that you fit to your car needs to be approved by the Clean Vehicle Retrofit Accreditation Scheme (CVRAS).

However, a visit to the Energy Saving Trust website highlights there are no retrofit emission control systems approved currently for pre-Euro 4 petrol vehicles and for pre-Euro 6 diesel cars. 

The organisation says they do not believe the systems will be available at any point in the future. 

There are a number of approved retrofit systems available for vans that use a selective catalytic reduction system, and this is added to the diesel particulate filter.

You'll need to check whether your van has an approved solution available because the system will be specific to the make and model.

Can I make my car ULEZ compliant?

While the answer to the question, ‘Can I make my car ULEZ compliant?' is ‘Yes', you will soon find that there are expensive obstacles in the way of achieving this.

Perhaps, the easiest way to comply if you have a non-compliant vehicle is to simply sell your car and buy a ULEZ compliant vehicle.

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