Class 4 & 4a MOTs Explained

MOT tests are a legal requirement in the UK, designed to ensure vehicles remain safe and roadworthy.

Among the different MOT categories, Class 4 MOTs are the most common, covering the majority of everyday vehicles.

There is also a closely related Class 4a MOT, which applies to a smaller group of passenger vehicles.

This guide explains what each class involves, the vehicle types included, the requirements, and the costs you can expect.

What Is a Class 4 MOT?

The Class 4 MOT is the standard test most drivers will be familiar with. It applies to a wide range of vehicles, including:

• Passenger cars with up to 8 seats
• Light vans and goods vehicles up to 3,000kg in design gross weight (DGW)
• Motor caravans and dual-purpose vehicles
• Private hire vehicles, such as taxis and ambulances with up to 8 passenger seats

During a Class 4 MOT, examiners check a comprehensive list of components to make sure the vehicle meets DVSA safety and environmental standards. These include:

• Brakes and suspension – ensuring effective stopping power and stable handling.
• Lights, indicators, and signalling equipment – confirming all are functional and correctly aligned.
• Steering and visibility – checking mirrors, wipers, and washers are in working order.
• Tyres and wheels – verifying tread depth (minimum 1.6mm across the central three-quarters) and condition.
• Seatbelts – ensuring they are present, secure, and working properly.
• Emissions and exhaust system – making sure levels fall within legal limits.
• Body structure – inspecting for corrosion or damage that could affect safety.

In short, a Class 4 MOT confirms your vehicle is safe to drive, properly equipped, and compliant with emissions standards.

What Is a Class 4a MOT?

The Class 4a MOT is essentially an extension of the standard Class 4 test.

It applies to passenger vehicles, motor caravans, ambulances, and dual-purpose vehicles that have 9 to 12 passenger seats.

The checks carried out are almost identical to a Class 4 MOT, but a Class 4a includes additional seatbelt inspections.

Vehicles in this category may be fitted with more seatbelts than the minimum required, so testers must confirm that every installation meets approved standards.

Aside from this focus on seating safety, a Class 4a MOT follows the same structure, requirements, and pass/fail criteria as a Class 4 MOT.
 

What Is the Difference Between Class 4 and 4a MOTs?

There are very few differences between the two.

The key points are:

• Class 4 MOT: Covers passenger vehicles with up to 8 seats, small vans, light goods vehicles under 3,000kg DGW, taxis, ambulances, and motor caravans.
• Class 4a MOT: Covers passenger vehicles, motor caravans, ambulances, and dual-purpose vehicles with 9 to 12 passenger seats, where additional seatbelt checks are required.

Other than the seatbelt inspection requirement, both MOT classes test the same safety, emissions, and roadworthiness standards.

Class 4 & 4a MOT Vehicle Types

Class 4 MOTs are by far the most common MOT class in the UK. If you drive a standard car, small van, or motorhome weighing under 3,000kg, this is the MOT you’ll need.

Vehicles covered include:

• Passenger cars (up to 8 seats)
• Dual-purpose vehicles
• Light vans and goods vehicles (under 3,000kg DGW)
• Motor caravans (under 3,000kg DGW)
• Private hire vehicles, including taxis and ambulances (up to 8 seats)
• Motor tricycles and quadricycles within weight limits

For Class 4a MOTs, vehicle types expand slightly to include:

• Passenger vehicles with 9 to 12 seats
• Motor caravans with 9 to 12 seats
• Ambulances with 9 to 12 seats
• Dual-purpose vehicles with 9 to 12 seats

Put simply, Class 4a covers the same vehicles as Class 4, but with a larger passenger capacity.

Class 4 MOT Requirements

The primary requirement for a vehicle to fall under a Class 4 MOT is weight.

Eligible vehicles must have a design gross weight (DGW) of up to 3,000kg.

Anything above this limit may fall into Class 7 instead, which applies to heavier vans and pickups between 3,001kg and 3,500kg.

Class 4a requirements are the same, except that the vehicle must also have between 9 and 12 passenger seats.

Both MOT classes are required every 12 months once the vehicle reaches the age when MOT testing becomes mandatory.

Typically, cars and light vans require their first MOT after 3 years, while taxis and ambulances usually require one after just 1 year.
 

How Much Does a Class 4 MOT Cost?

The maximum DVSA fee for a Class 4 MOT is £54.85. Garages may choose to charge less, often as part of a promotional offer or when combined with a service.

It’s important to note that this fee only covers the MOT test itself. If your car fails its MOT and requires repairs or replacement parts, additional costs will apply.

Keeping up with regular car servicing can help minimise the risk of unexpected repair bills when your test is due.

How Much Does a Class 4a MOT Cost?

A Class 4a MOT costs the same as a Class 4 MOT. The DVSA sets the same maximum fee of £54.85, and again, garages may discount this price.

Since the checks are almost identical, including the seatbelt inspection, there is no price difference between Class 4 and Class 4a MOTs.

Book Your Class 4 MOT Through Blackcircles.com Today

Blackcircles.com now offers MOT bookings online without the need to purchase tyres at the same time.

Simply enter your registration to find local approved MOT test centres and book directly.

Staying on top of your Class 4 or Class 4a MOT will keep your vehicle roadworthy, safe, and legally compliant.