How Much Does A Catalytic Converter Replacement Cost in the UK?

A catalytic converter is a device that is fitted to the exhaust system of a car. It helps to reduce the emissions of harmful gases from the engine by converting them into less harmful gases. Over time, the converter can become clogged with deposits or damaged internally, reducing its efficiency. When this happens, it needs to be replaced. A catalytic converter is a legal requirement in the UK and drivers can be fined if caught driving without one.

Catalytic converters are usually a target for thieves because they contain precious metals, typically platinum, rhodium or palladium, that can be sold for a high price.

How much does it cost to replace a catalytic converter?

The average cost of replacing a catalytic converter is £310, with prices ranging from £175 and £900. If the catalytic converter replacement job is a result of a theft of the part, then more often than not there is additional damage caused by the thieves during the process of removal which may increase the cost of the replacement. The exact price of the catalytic converter depends largely on your car and the parts recommended by the manufacturer.

Your location can also be a key factor in determining the price of a catalytic converter replacement. For example, average hourly labour rates and demand in cities like London is around £50-£100 while in towns with lower demand, the labour rates can range from £35-£50. The type of mechanic, for example, a mobile mechanic vs a dealership garage technician can also affect the total cost of a catalytic converter replacement.

Average cost of a catalytic converter replacement by location

To avoid having car owners overpaying and get a fair price for a catalytic converter replacement, we use real-time data of thousands of car makes and model data, local labour prices for catalytic converter repairs and replacements and part prices to provide an instant fair quote. Simply enter your vehicle registration number and postcode to get an instant price for a catalytic converter replacement for your car.

Average cost of a catalytic converter replacement by manufacturer

Signs your catalytic converter needs to be replaced

• Check engine light
• Reduced acceleration
• Noticeable decrease in engine power
• Rattling noise from exhaust area
• “Rotten egg” or sulfuric smell from exhaust
• Dark smoke from exhaust
• Low fuel efficiency
• Emissions test failure
• Stolen catalytic converter (will need to be replaced as it is illegal to drive without one in the UK)

Check engine light

Among other things, the check engine light on the dashboard can indicate an issue with the catalytic converter

Dark smoke from exhaust

If you notice thick dark smoke emitting from the exhaust, it is likely to be caused by a broken catalytic converter. It is often accompanied by reduced engine performance.

Increase in fuel consumption

A clogged catalytic converter will likely result in exhaust being blocked - this will result in a decrease in fuel efficiency.

Smell of rotten eggs from exhaust

A smell of rotten eggs coming from a car's exhaust system is typically an indication of a problem with the car's fuel filter system or more commonly the catalytic converter.

Frequently asked questions about catalytic converter replacement cost

Can you drive a car if the catalytic converter is broken?

Yes, you can technically drive a car with a broken catalytic converter, however, it is illegal to do so as harmful emissions and toxic pollutants are released into the environment as a result. Driving without a catalytic converter can land you with a fine of up to £1000!

What does a failing catalytic converter sound like?

​​A failing catalytic converter can sound like a rattling noise or a loud muffled thumping under the vehicle.

What happens if someone steals your catalytic converter?

If you notice that your catalytic converter has gone missing as a result of theft, the first thing to do is check with your insurance provider if theft is covered. By making a claim, you may risk losing your no-claims bonus and paying higher car insurance premiums but it is still worth checking and weighing your options. The cost of replacing a catalytic converter after a theft can sometimes go into the £1000s due to the damage caused by the thieves. In some cases, especially with older cars, the damage caused may be too great and the car is written off as a result by the insurance company.

How long does a catalytic converter replacement take?

On average, catalytic converter replacement times can range from just over 1 hour to 1.7 hours with an average of around 1.2 hours. The time that the job takes will depend on a number of factors, like your vehicle's make and model, year, as well as other factors. Select your car at the top of this page for information on job time and cost for your vehicle through ClickMechanic.

Can I carry out a catalytic converter replacement myself?

Replacing a catalytic converter is a complex job and requires advanced knowledge of vehicle exhaust systems. It involves working with multiple sensors and calibration and using specialised tools such as exhaust pipe cutters, wrenches, and lift equipment.

Unless you are a qualified mechanic with the required skills, training and equipment to do the job, we strongly recommend a catalytic converter replacement is only carried out by a professional mechanic. ClickMechanic can help get you a vetted and local mechanic to carry out the work. Just enter your postcode and your car's registration number at the top of this page and select the work needed to get an instant fixed price up front.

What else could be the problem if my catalytic converter isn’t broken?

If you’re experiencing symptoms that point to catalytic converter issues and you’ve ruled it out, it could one or more of the following:

• Oxygen sensor - malfunctioning or faulty oxygen sensors can lead to poor fuel efficiency, reduced engine performance, and other symptoms that might resemble catalytic converter problems
• Exhaust leak - leaks in the exhaust system, such as at the exhaust manifold can cause noise, poor engine performance
• Fuel system issues - faulty fuel injectors, fuel pressure regulator, or fuel pump can cause poor engine performance and misfires
• Clogged air filter - sometimes a dirty air filter can restrict the airflow, resulting in a rich mixture. This can result in a rotten egg or sulfuric smell

What happens during a catalytic converter replacement?

• Mechanic will read the ECU for catalytic converter and oxygen sensor-related problems.
• Mechanic will inspect the catalytic converter for damage.
• Mechanic removes oxygen sensor for further check and removal of catalytic converter.
• If necessary, the catalytic converter will be replaced.
• Mechanic will advise if other parts need to be replaced.
• Mechanic will run engine, check catalytic converter operation.
• Mechanic will make adjustments where necessary.