Motorists driving into London from today could be hit with new charges as the capital extends its Ultra Low Emissions Zone.

The boundaries of the area, within which vehicles that don't meet particular environmental standards must pay to enter, are widening. Here's all you need to know about the changes.

What is the Ultra Low Emissions Zone?

Known as ULEZ, the capital's emissions zone is an area of London through which drivers of cars that are deemed not to be environmentally friendly must pay to travel in.

The ULEZ operates 24 hours a day, seven days a week, with the only exception being Christmas Day when charges are not enforced.

Why does it exist?

The ULEZ is there to reduce the capital's carbon emissions. Charging the most high polluting vehicles to use the roads, it is hoped, discourages drivers from bringing their vehicles into the city and persuades them instead to use public transport or where vehicles are necessary – that more eco-friendly options are adopted.

And according to the Mayor of London's office the policy works. Figures suggest, it says, that before the pandemic the ULEZ contributed to a 44% reduction in harmful roadside nitrogen dioxide levels within the zone and 44,000 fewer vehicles travelling within the designated area.

Why is it expanding?

Pollution, says the Mayor of London's office, is not just a central London problem and all Londoners live in areas exceeding World Health Organisation guidelines for the most dangerous toxic particles.

And so the size of the zone is being increased to try and improve the air quality for more people living, working or visiting the capital city – and in turn improve their health.

Officials say 'toxic' air pollution remains the biggest environmental health risk to all Londoners, with an estimated 4,000 people, says the London Assembly, dying prematurely in 2019 because of long-term exposure to air pollution.

What's changing?

From today, London's ULEZ will expand from Central London up to – but not including – the North Circular and South Circular roads.

The area covered by today's expansion, say officials, is 18 times larger than the original Ultra Low Emissions Zone.

Four out of five cars driving in the expanded ULEZ on an average day are already estimated to be compliant, say officials. And if you walk, cycle or take public transport through the capital you won’t need to make any changes.

Who is affected and how much will it cost?

If you drive into London, or own a vehicle and live within the new zone you can use the Transport for London free online vehicle tracker to see if you are affected by the ULEZ expansion.

Entering your number plate into the site will explain to you whether you will need to pay to use the expanded zone or whether your car's emissions fall below the threshold for being charged. You will also not be charged for a non-compliant vehicle that is simply parked in the zone on days you don’t drive it.

Drivers of cars, motorbikes and some vans that don’t meet the emission standards must pay the daily ULEZ charge to drive in the zone, which is £12.50 for most vehicles but £100 for much heavier vehicles.

However there are some separate rules for heavy vehicles including vans, lorries, coaches and buses as they will need to meet Lower Emission Zone standards instead of the ULEZ guidelines.

While the emission standards are mostly the same, the areas covered are different and the charges higher. To learn more about those, and whether your type of larger vehicle is affected, click here.

How to pay

Drivers can pay in advance or on the day and if you forget to pay your charge you have up to midnight three charging days after you have travelled to settle your balance in order to avoid a fine.

There is also the option to set up Auto Pay with TfL which will automatically take a payment.

But those caught not paying for vehicles, which aren't exempt from daily ULEZ charges, risk being sent a penalty charge notice where fines are £80 or more.

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