London’s Congestion Charge (CC), Low Emission Zone (LEZ) and Ultra Low Emission Zone (ULEZ)

Context of Transport Climate Action

In February 2003 the Congestion Charge (CC) scheme was introduced in Central London to reduce traffic volumes and congestion. It operates between 7am and 6pm on weekdays and covers a small area in central London.

The Low Emission Zone (LEZ) scheme was first introduced 2008 and aims to improve air quality by reducing exhaust emissions from the most polluting vehicles. The LEZ covers most of Greater London and operates 24 hours a day, 7 days a week. The Ultra Low Emission Zone (ULEZ) will be introduced in 2020 in the same area as the Congestion Charging Zone (CCZ) in central London. This is the area with the greatest human exposure to poor air quality and the area in which road transport emissions may be most effectively tackled. It will require all vehicles travelling in the zone to meet emissions standards or pay a charge. Like LEZ, ULEZ will operate 24/7.

Description of the schemes – CC, LEZ, and ULEZ

Congestion Charge Scheme (CC)

The Congestion Charge was introduced to Central London on 17th February 2003 – the size of the zone is 21sq km.

The scheme has been designed to encourage private motorists to use other modes of transport and has helped London become the only major city in the world to observe a modal shift away from private car use to public transport, walking and cycling.[1]

ANPR (Automatic Number Plate Recognition) cameras read a vehicle’s number plate as it enters, leaves or drives within the charging zone. This is then checked against the DVLA database (Driver and Vehicle Licensing Agency) and non-exempt vehicles are required to pay the daily charge of £11.50 (2015 rates) for driving a private vehicle within the charging zone between 07:00 and 18:00, Monday to Friday. There are a range of exemptions and discounts available to certain vehicles and individuals.

The introduction of the CC scheme has helped contribute to an overall reduction in vehicle kilometers within the CC zone of 23 per cent between 2000 and 2012. This has helped release road capacity which has allowed TfL and the central London boroughs to improve the urban environment, increase road safety and prioritise public transport, pedestrian and cycle traffic.

Congestion charging continues to make a valuable contribution to London’s transport network. While levels of congestion in central London are now close to pre-charging levels, the effectiveness of the congestion charge in reducing traffic volumes means that conditions would have been far worse if the Congestion Charging scheme were not in place, and the revenues from the charge have been useful for reinvestment into low carbon options.


Low Emission Zone (LEZ)

The Low Emission Zone (LEZ) was introduced to restrict the most polluting vehicles from driving into London.

The LEZ became operational on 4th February 2008 and covers most of Greater London (with minor deviations to allow diversionary routes and facilities to turn around without entering the zone). The size of the zone is 1,580 sq km making it much larger than the CC zone (map available at the following link:

The LEZ operates 24 hours a day, 7 days a week and is marked by signs. The LEZ emissions standards are based on European emission standards relating to particulate matter (PM), which are emitted by vehicles and which have an effect on human health. The charges only apply to the most polluting large vehicles, cars are not affected. A full list of the vehicles affected can be found at the following link:

There are no barriers or toll booths within the LEZ. Instead, ANPR cameras and mobile cameras are used to read number plates which are then checked against a database of registered vehicles.

This database is compiled using information from the DVLA, generic vehicle weight data typical of the make and model, and drivers and operators who have registered with the scheme.

Since the introduction of LEZ phases 3 and 4 in January 2012, 97% of all vehicle types have met the standards introduced.

Ultra Low Emission Zone (ULEZ)

London’s air quality has improved significantly in recent years and Is now compliant for all but one air pollutant for which the EU has set legal limits. This pollutant is nitrogen dioxide (NO2), which can irritate the lungs and cause increased incidence of acute respiratory illness in children.

As a result of fuel duty and new-car CO2 targets for car manufacturers new diesel car sales in the UK have increased, from an approximate 14% share in 2000 to 50% in 2012.

Whilst the uptake of diesel vehicles has helped reduce CO2 emissions, it has also led to more air pollutants being emitted. The ULEZ has been designed in order to address this ‘dieselisation’ of London’s fleet.

Roughly 4,300 deaths in London per year are attributed to air quality related illness. At the same time London also faces challenging targets to mitigate the effects of climate change.

It is the responsibility of the UK Government, London Boroughs and the Mayor to take action in order to meet EU air quality limits. TfL are introducing measures to promote more walking, cycling, use of public transport and to encourage sustainable freight deliveries. ULEZ is another way to further reduce the most harmful road transport generated emissions in central London and across the Capital.

The ULEZ will be introduced on 7th September 2020 and operate 24 hours a day, 7 days a week in the same area (21km square zone) as the current Congestion Charging Zone. All cars, motorcycles, vans, minibuses and Heavy Goods Vehicles (HGVs) will need to meet exhaust emission standards (ULEZ standards) or pay an additional daily charge of £12.50 or £100 (depending on the vehicle type) to travel within the zone. Similarly to CC and LEZ, ANPR cameras will read vehicle number plates in order to gauge whether the vehicle meets the LEZ emissions standards, is exempt, is registered for a discount, or if the daily charge has already been paid.

The majority of traffic entering the ULEZ will be from outside the zone – so the benefits of cleaner, greener vehicles in the form of reduced emissions will be delivered right across Greater London, even to areas not in the zone. See table below:

ULEZ     Inner London Outer London
CO2 -14% -3% -0.5%
NO2 -47% -18% -10%
NOx -49% -18% -10%
PM 10   -47% -13% -1%
PM 2.5   -48% -13% -2%

Source: (Table 8)

Motorcycles will need to be EUR 3; cars, vans and minibuses either EUR 4 petrol or EUR 6 diesel; and HGVs and buses/coaches EUR VI to be exempt. Motorcycles, public service vehicles such as ambulances, fire service and taxis do not need to pay the CC but all vehicles are expected to comply with the ULEZ.

There are a number of incentives in place to help provide support for the introduction and purchase of new vehicles:

  • All 300 single decker buses operating in the ULEZ are zero emission (e.g. electric), and all 3,100 double deck buses will be hybrid by 2020.
  • All taxis new to licensing from January 2018 and new PHVs new to licensing from January 2020 to be Zero Emission Capable (ZEC) [2]. In light of concerns raised by the taxi and PHV trade organisations a voluntary decommissioning scheme for taxis older than 10 years is to be introduced (instead of the reduction in the age limit to 10 years originally proposed).

The Office for Low Emission Vehicles (OLEV) currently offers grants towards the purchase of ultra-low emission vehicles (up to the value of £5k). The OLEV also intends for local authorities to be able to top-up this grant when it is claimed towards the purchase of a ZEC taxi (the top-up grant is not available for PHVs however). London has been awarded a £25m fund by National Government in support of this initiative, which will enable TfL to distribute top-up grants to London taxi drivers. In total, it is proposed that grants of up to £8,000 are offered towards the purchase of a ZEC taxi from mid-2017 until 2020.

The Future of ULEZ

TfL are engaging with London Boroughs to understand how best to expand ULEZ after 2020. This feasibility work is in addition to TfL and the Mayor’s continuing work to drive down emissions.

Benefits and Potential Scaling Up

The introduction of low emission and ultra low emission zones can be scaled up into many cities especially those that have historic centres that can be more easily served by a limited number of cameras.

[2] Public consultation from July to August 2015

Selected references



London, UK


Congestion Charge (2003), Low Emission Zone (2008), Ultra LEZ (2020)


All schemes are ongoing


UK, Mitigation, Policy, Passenger, Frieght


Transport for London (TfL)


Sam Longman Policy Manager for Environment Strategy and Planning, TfL