Almost 700,000 drivers in London will have to pay the £12.50 ultra-low emission zone (Ulez) levy if they use their car when the scheme expands, according to new analysis.

The RAC, which obtained the figures from the Driver and Vehicle Licensing Agency (DVLA), said the expansion of the zone from August 29 would have a “massive financial impact on motorists and businesses”.

The London mayor’s office has disputed the figures — while Transport for London (TfL) has claimed nine out of 10 cars seen driving in outer London on an average day meet the Ulez standards.

But the RAC figures are the first to show the total number of non-compliant cars registered to London addresses — including many homes already inside the current Ulez zone.

Aimed at improving air quality, the Ulez scheme will be expanded to include outer London from August 29.

Last month, five councils joined forces to file a lawsuit in an effort to block the Ulez expansion.

What is the Ulez and how many Londoners will it affect?

The ultra-low emission zone is an area of London that more polluting vehicles have to pay to enter.

It’s a bit like the congestion charge zone — only much bigger. And if Mayor Sadiq Khan gets his way, the Ulez will cover all of Greater London by the end of August this year.

Put simply, if you drive an older petrol or diesel car, you have to pay TfL £12.50 for every day you cross into, or move within, the Ulez zone.

Mr Khan launched the Ulez in central London in 2019. Two and a half years later, it expanded up to the edge of the North and South Circular Roads.

But the mayor wants to expand it for a second time across all 33 London boroughs — effectively taking it up to most roads inside the M25 motorway.

Why does Sadiq Khan want to expand the Ulez?

In his mind, it’s all about health. He wants to clean up London’s air. He claims five million more Londoners will breathe cleaner air if the Ulez expands for a second time.

He often quotes research from Imperial College, which estimated that in 2019 between 3,600 and 4,100 premature deaths in London were due in part to the poor air quality.

But in 2021, new research from Imperial concluded that the central London Ulez was responsible for “only small improvements in air quality” — and there was already a longer-term downward trend in toxic air levels.

They said Ulez on its own was not an effective strategy to improve air quality — and that it worked “best” alongside other policies to reduce emissions.

Will the Ulez expansion actually clean up London’s toxic air?

This is the key issue — and it’s not easy to answer.

Independent experts Jacobs, who were commissioned by TfL, say there is likely to be a “moderate positive impact” on nitrogen oxide emissions — those from exhaust pipes — and a “minor positive impact” on PM emissions, the tiny soot particles from diesel engines, tyres and brakes.

Overall, the Ulez is expected to deliver a “minor positive impact” on Londoners’ health. This is according to a summary of the research by the House of Commons library.

Mr Khan believes the Greater London Ulez expansion will reduce nitrogen oxide emissions from cars in outer London by 10 per cent, and from vans by seven per cent.

About half of nitrogen oxide emissions in London come from road transport. The remainder come from factories, construction sites, homes and offices, river transport and planes.

As for PM particulates, about 31 per cent of these in London come from road transport. PM levels often depend on the weather — particles can get blown in from mainland Europe. Mr Khan believes the Ulez will reduce PM emissions from exhausts by 16 per cent.

What’s the latest data on the Ulez?

TfL’s most recent report looks at the impact of the Ulez in the first year after it expanded to the boundaries of the North and South Circular roads. This found a 60 per cent reduction in the number of “non-compliant” vehicles being driven into or within inner London.

But it also included data showing that levels of nitrogen dioxide in central London were rising. These was blamed on an increase in traffic post-pandemic, though the relaxation of the congestion charge’s operating hours may also be a factor.

The report also showed the percentage reduction in nitrogen dioxide in the suburbs was far less dramatic than that seen in central London.

How many more people will have to pay the Ulez levy?

At present, about 35,000 drivers pay the Ulez each day.

But when it expands again, almost 700,000 drivers in London will have to pay the £12.50 ultra-low emission zone (Ulez) levy if they use their car, according to the RAC.

TfL estimates about 200,000 more drivers will have to pay each day.

Who has to pay?

If you’re driving a petrol car with what’s known as a “Euro 4” engine — that is, all cars built since 2006 — or a diesel with a “Euro 6” engine, which came in from 2014, then you won’t have to pay the Ulez.

If your car is older — ie, if you have a petrol car more than 16 years old, or a diesel more than seven years old — you may have to pay. Check your number plate on the TfL website.

About 85 per cent of vehicles in the new Greater London zone already comply with the emission rules and won’t have to pay.

How many people are opposed to the Ulez?

It’s very hard to be sure. Almost 58,000 people or organisations responded to a TfL consultation in the summer of 2022.

A majority — 59 per cent — said the Ulez should not be expanded across Greater London.

But Mr Khan believes the consultation was “hijacked” by pro-car lobby groups and motorists living outside London.

He points to an opinion poll of 1,200 Londoners commissioned by City Hall, which found 51 per cent support for the expansion.

More recently, there has been something of a backlash against the Ulez from a number of outer London councils.

Four Tory boroughs — Harrow, Hillingdon, Bexley and Bromley — have threatened joint legal action. They had until the end of February to decide whether to ask the High Court to intervene.

The boroughs say the Ulez will do little to improve air quality — and is being introduced at the worst possible time, because of the cost of living crisis.

Other councils say they support efforts to clean up the air — but want Mr Khan to delay, to give drivers more time to switch cars.

Some councils say they won’t allow TfL to erect Ulez cameras on their roads. Others outside London say they will refuse to allow Ulez signs to be erected.

Has the Ulez changed the type of cars being driven in London?

Yes — quite markedly. Before the Ulez was expanded to the suburbs in 2021, 87 per cent of vehicles complied with the rules — meaning 13 per cent had to pay the levy.

But a year later, the compliance rate had shot up to 94.4 per cent. This gave clear evidence that the “short, sharp shock” of having to pay £12.50 a day was forcing drivers to upgrade their vehicles — or avoid travelling into the zone.

The number of diesel vehicles within the zone fell by 63 per cent in 12 months — that’s 50,000 fewer diesel cars a day.

Is Mr Khan offering any help to Londoners wanting to upgrade their car?

Yes — a £110m scrappage scheme opened in January. This will offer low-income Londoners a £2,000 grant to scrap their car, or to help them buy one that complies with the Ulez rules.

But don’t hang around — there’s only enough cash to help about 30,000 people.

What happens if you don’t pay the Ulez?

Bad news: you get sent a £180 fine in the post. TfL admits thousands of motorists are running up huge debts by failing to pay — a problem it attributes to the cost of living crisis.

It’s important to remember that the Ulez doesn’t apply only to Londoners — but also anybody driving into or within the capital in a vehicle that breaches the exhaust emission rules. This includes foreign drivers.

Put simply, if you’re driving a more polluting vehicle in London — what we used to call an “old banger” — then you’re going to have to pay.