Portsmouth Clean Air Zone (CAZ) – the ultimate guide

    Portsmouth maintains the only charging Clean Air Zone (CAZ) on the United Kingdom’s south coast. Part of the UK’s commitment to environmental sustainability, these CAZs are designed to improve air quality by reducing harmful emissions from cars, vans, and other vehicles in urban areas. 

    In Portsmouth, the CAZ discourages older, high-polluting vehicles from entering certain city areas by charging them for driving through the designated zone. Unlike in other CAZs across the UK, passenger cars and vans are not charged. 

    Understanding the specifics of your local CAZ is essential for anyone owning, buying, or looking to sell a car. Our comprehensive guide tells you all you need to know about Portsmouth’s emissions policies, helping you get the most out of your vehicle investments.

    What is a Clean Air Zone (CAZ)?

    Clean Air Zones are areas where vehicles must comply with set emissions standards or face a penalty.

    To reduce air pollution and improve public health, the UK government is working with local councils to implement Clean Air Zones (CAZ) across the country. 

    In addition to Low Emissions Zones, such as the ULEZ in London, and Zero Emissions Zones, there are currently seven other cities with designated CAZs: Bath, Birmingham, Bradford, Bristol, Sheffield, Tyneside (encompassing Newcastle and Gateshead), and York.

    CAZs are divided into four classes: 

    ClassVehicle type 
    ABuses, coaches, taxis, private hire vehicles
    BBuses, coaches, taxis, private hire vehicles, heavy goods vehicles (HGVs)
    CBuses, coaches, taxis, private hire vehicles, HGVs, vans, minibuses
    DBuses, coaches, taxis, private hire vehicles, HGVs, vans, minibuses, and cars
    Local authority has the option to include motorcycles

    Any running a CAZ has the same minimum emissions compliance standards:

    Vehicle typeCAZ minimum standard
    MotorcyclesEuro 3
    Vans, minibuses, taxis, private hire vehicles, carsEuro 4 (petrol engine) and Euro 6 (diesel engine)
    Buses, coaches, heavy goods vehiclesEuro VI
    Battery Electric Vehicles (BEVs)Automatically compliant

    If your vehicle exceeds a zone’s emissions standards, you may have to pay a fine to drive through the area. Penalty costs for non-compliant vehicles are handled by local councils.

    What is the Portsmouth CAZ?

    After the UK government identified Portsmouth as one of 60 local authorities where air pollution exceeds legal limits, the city introduced a Class B Clean Air Zone in November 2021. Over 50% of the city’s air pollution is a direct result of vehicle emissions. 

    To help improve the health of Portsmouth residents, visitors, and the surrounding natural environment, the city’s CAZ charges a daily fine to high-emission vehicles when driving through the city centre. 

    In Portsmouth, non-compliant vehicles are defined as older Heavy Goods Vehicles (HGVs, including some larger motorhomes), buses and coaches, taxis, and private hire vehicles that do not meet Euro 6 emissions standards for diesel, or Euro 4 standards for petrol. 

    Private passenger cars are not subject to CAZ charges. 

    Where is the Portsmouth CAZ?

    (Image from the map of Portsmouth CAZ)
    The Portsmouth CAZ covers central Portsmouth, down to the ferry terminals.

    The boundaries of the Portsmouth CAZ are designated by the Portsmouth City Council. The zone is approximately 3km2, and is located across the south west of Portsmouth. The CAZ includes the city centre, Portsmouth Harbour, Portsea, Landport, and Somers Town neighbourhoods. 

    Portsmouth International Port is outside of the CAZ charging area. The port is governed by other government clean air regulations.

    Explore detailed maps of Portsmouth CAZ for more detailed information, as well as to see if your postcode falls within the CAZ. 

    What vehicles are affected by the CAZ?

    As a Class B CAZ, the Portsmouth zone charges non-compliant HGVs, buses, coaches, taxis, and private hire vehicles if they do not meet Euro 6 emissions standards (for diesel) or Euro 4 standards (for petrol). 

    These high-emission vehicles are likely to be older and may have been built before the latest Euro emissions standards were established. Some motorhomes are also charged under Portsmouth’s CAZ; if you own a motorhome, we advise checking your vehicle’s status before heading into central Portsmouth as the DVLA classifies some motorhomes as HGVs.

    Non-compliant vehicles are charged on a daily basis for going through the city’s CAZ: 

    Vehicle typeDaily charge
    Private cars, motorcycles, vansNo charge in Portsmouth
    *but may be subject to other CAZ charges across the country
    Non-compliant taxis and private hire vehicles£10
    Non-compliant HGVs, buses, and coaches£50

    Portsmouth’s CAZ is enforced through monitoring systems, such as Automatic Number Plate Recognition (ANPR), and signage indicating entry and exit points. 

    CAZ exemptions

    Newer, compliant vehicles, as well as personal passenger cars and vans, are not charged under Portsmouth’s CAZ scheme. 

    If you’re unsure what Euro emissions standard your vehicle is, check your V5C logbook or try our ULEZ tracker tool, which also covers CAZs across the country. 

    Future sustainability efforts in Portsmouth

    In addition to the CAZ, Portsmouth is actively pursuing other initiatives to become a greener and more sustainable city.

    The city is also investing in sustainable transportation infrastructure. This includes installing more electric vehicle (EV) charging points across the city and piloting eco-friendly transport options, such as e-scooter trials and bikeshare schemes. 


    Do I need to pay for the CAZ in Portsmouth?

    CAZ payment depends on your vehicle’s emissions. High-emission vehicles, including HGVs, buses, coaches, and taxis, will likely incur charges when entering the zone. Passenger cars and vans are not affected by the CAZ.

    Check your vehicle’s compliance with our ULEZ tracker tool; the results are also valid for CAVs across the country.

    Why are passenger cars not charged in the Portsmouth CAZ?

    According to Portsmouth City Council’s modelling, the city’s Class B CAZ (which only charges buses, coaches, taxis, private hire vehicles, heavy goods vehicles) is likely to be sufficient in reducing air pollution in the least amount of time. 

    However, the exact bounds of the CAZ are subject to change.

    Is Portsmouth harbour in the Clean Air Zone?

    Yes, Portsmouth harbour falls within the city’s CAZ. Vehicles must abide by emission-related regulations while driving through the zone or face charges. 

    However, Portsmouth International Port and Portico are outside of the CAZ.

    Will Portsmouth expand its CAZ?

    As of now, there are no current plans to expand the Class B Clean Air Zone in Portsmouth.

    How can I sell a non-compliant vehicle?

    If your vehicle is non-compliant with national or local emissions standards, you can still sell it and invest in a compliant car or van. 

    At Motorway we offer a simple – and completely free – method of getting the best price when selling your vehicle, whatever the model. Just enter your reg on our homepage for an instant estimated sales price based on up-to-the-minute market data. We’ll then ask you a few easy questions about your car and guide you through building your vehicle profile. Remember to note that your car’s non-compliant! 

    This can be done right from your phone, in just a matter of minutes.

    You can choose to enter your car into our daily sale, where it will be shown to our nationwide network of 5,000+ verified dealers looking to add to their stock of used cars. Interested dealers will compete to buy your car, offering you their best price.

    In as little as 24 hours you’ll receive your best offer – and, if you choose to go ahead with the sale, your car will be collected for free by the dealer and the money will be quickly and securely transferred to your bank account.

    Ready to sell your car?

    Read about everything you need to know about how to sell your car with more guides here. There’s a lot to learn about Clean Air Zones and UK emissions standards ahead of the 2035 electric switchover.