After months of challenges, London Mayor Sadiq Khan's plan to create the world's largest low-emission zone has finally come into being.

As of 29 August, owners of certain vehicles face a daily £12.50 charge to drive in any part of London, and a £180 penalty for failure to pay.

Known as the ultra-low emission zone (ULEZ), the policy aims to improve air quality in London by charging heavy polluting vehicles on the roads.

ULEZ was first implemented in 2019, covering London up to, but not including, the North and South (A406) roads. It now includes the outer capital and borders the surrounding counties of Surrey, Essex, Hertfordshire, Kent, Berkshire and Buckinghamshire.

Almost 850,000 vehicles in London are no longer ULEZ compliant, including 700,000 cars, according to analysis by the Royal Automobile Club (RAC). However, the expansion affects only 10% of cars in outer London, according to the London Assembly.

Is your vehicle ULEZ compliant?

Whether or not a vehicle is ULEZ compliant is based on European standards of emission, and can be checked for individual vehicle types on the Transport for London (TfL) website.

To be exempt, petrol cars must be rated at least Euro 4 for NOx, while diesels must be rated Euro 6 for NOx and PM. TfL said petrols first registered before 2006 and diesel cars registered after September 2015 will likely pass these standards.

For motorcycles and mopeds, ULEZ is enforced on vehicles that do not meet Euro 3 emissions standards for NOx. Generally, Euro 3 engines are those registered with the Driver and Vehicle Licensing Agency after July 2007.

Small and large vans must meet Euro 4 and Euro 6 standards for petrol and diesel respectively to be exempt from ULEZ. All new diesel vans sold from September 2016 should meet the Euro 6 standard, and all new petrol vans from January 2006 should meet the Euro 4 standard, according to TfL.

Lorries, vans and specialist vehicles above 3.5 tonnes do not need to pay the ULEZ charge.

ULEZ tax relief and vehicle replacement subsidies

To help Londoners switch from non-compliant vehicles, owners of non-compliant cars can get £2,000 for scrapping their vehicle, while motorcycle owners can get £1,000.

Small businesses and charities can receive increased grant payments of between £6,000 and £11,500.

The grant for scrapping a non-compliant van is £7,000, while there is a £9,000 subsidy for purchases of electric vans.

The payment for wheelchair accessible vehicles has increased from £5,000 to £10,000, with grants of £6,000 available to retrofit a van to ULEZ standards.

However, businesses and charities can only apply for grants until 29 November 2023 for retrofits and 29 February 2024 for new vehicles.

HMRC also confirmed that ULEZ charges incurred for business purposes can be deducted from businesses' tax bills. It said:

"Self-assessment customers are entitled to tax relief on travel expenses, including low emission zone charges, if they have been exclusively for the purposes of the trade.

"When a self-employed individual claims an allowable expense, the amount is deducted fully from their taxable profits."

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