How much does it cost to replace a catalytic converter in the UK?

Although your car can still run even when the check engine light comes on, it’s important to bring it to a mechanic to find out what the issue is. You might already be facing a serious problem, like a failing catalytic converter. If the mechanic confirms it, you’ll need to prepare for a significant bill. The catalytic converter replacement cost can range from £175 to over £2,000.

To help you understand what to expect, this guide breaks down the factors that affect the price. You’ll know what to budget for and how to fairly assess the quoted repair.

What are the average costs of replacing a catalytic converter in the UK?

How much is a new catalytic converter? Prices can vary widely, depending on the location. Urban areas like London and Edinburgh often have higher replacement costs due to a higher cost of living and shop overhead. While prices can be lower in regional and remote areas, these areas often face challenges sourcing parts, so expect extra charges for deliveries. 

*City figures are indicative estimates based on recent Airtasker UK pricing signals combined with current national catalytic converter replacement benchmarks. Actual costs may vary considerably.

What factors affect the cost to change catalytic converters?

Mechanic handling a used catalytic converter in an open engine bay (Source: Shutterstock)

Aside from location, several other factors can affect the final price of a  catalytic converter: 

Vehicle make and model

Your car’s make and model can affect the cost to install a catalytic converter. For instance, if you own a luxury vehicle (like a BMW or Range Rover), expect higher prices since these are often high-performance cars that use a more premium precious platinum group of metals (PGMs), which is 60–100% more than standard converters in small hatchbacks. These PGMs consist of platinum, palladium, and rhodium, and they work as metals to clean your exhaust and reduce emissions. 

Type of catalytic converter

Different types of catalytic converters are available to fit a car owner’s needs and budget. Universal aftermarket converters are the most affordable choice (priced between £200 and £450), but the trade-off is installation. They require cutting and welding, which adds significant labour costs. More importantly, universal converters often don’t meet Type Approval standards, so they may not pass an MOT emission test.

A direct-fit aftermarket converter can be a great alternative because, although it costs more upfront, its bolt-on design makes installation easier, thereby lowering labour costs. However, if reliability is your priority,  investing in an Original Equipment Manufacturer (OEM) converter is a wise choice. It’s the most expensive, priced between £600 and £1,200, but you get guaranteed quality and a manufacturer’s warranty.

Check out this table that shows the  typical catalytic converter prices in the UK for different types:

Number and location of catalytic converters

The price of a catalytic converter can also depend on the number and location of your catalytic converter. If it’s a single bolt-on converter located underneath the vehicle. If it’s built into the exhaust manifolds, installation can be more difficult because it requires the mechanic to work in tight engine bays. They might need to spend extra hours and provide additional services, such as exhaust repairs, which increases labour costs.

Installed catalytic converter connected to vehicle exhaust piping (Source: Shutterstock)

Prices can increase further if your car has more than one catalytic converter. This is common for vehicles with V6 and V8 engines because they’re typically built with dual exhaust systems to help the engine run more efficiently and produce more power. Trucks and high-performance vehicles are also great examples, as they typically have large engines that require 3 to 4 converters.

Meanwhile, integrated converter-manifold units in modern hybrids like the Toyota Prius are the most expensive to install and replace. Their integrated design makes them more complex, since they’re built directly into your car’s exhaust manifold. This means that the technician can’t separate the converter from the manifold, so the entire manifold must be assembled and replaced if the converter fails.

The table below shows price ranges by the number and location of catalytic converters, so you can see the cost differences at a glance.

Labour and installation complexity

As with any other service, the cost of replacing a catalytic converter rises as the job gets more complex. Simple bolt-on replacements are the most affordable, since they often take only 1 to 2 hours to complete, as shown in our table below.

Expect prices to increase further if additional labour is needed, such as removing and refitting parts, or if some welding is required, probably because they used a universal converter.

Labour costs can also push to £200 to £350 when corroded and seized components, such as rusted bolts, stuck oxygen sensors, and broken studs, extend the job by more than an hour. It’s even more expensive for catalytic converters that require a complex manifold-integrated replacement, since, as we said earlier, this means replacing both the manifold and the catalytic converter.

Additional repairs or replacement parts

Mechanic inspecting an oxygen sensor and electrical connection (Source: iStock)

Often, when one part of the vehicle fails, other parts also malfunction, requiring extra labour and replacement. So, if the mechanic suspects it’s a catalytic converter issue, it’s also likely that it’s an oxygen sensor failure. 

These sensors fail more frequently than converters and produce the same P0420 warning light, so they’re often mistaken for the same issue. This is why it’s always recommended to have a proper diagnostic test first, which may incur additional charges.

However, if the mechanic or technician confirms it’s a catalytic converter issue, expect to also cover engine problems such as a blown head gasket, worn piston rings (oil burning), or a spark plug/ignition coil issue. These are the main causes of damage and contamination of catalytic converters, so they must be resolved before replacing or installing a new converter.

Other repairs, like those in the exhaust system, such as the manifold and pipes, are equally important to consider, too, especially if they’ve become rusted or cracked. Leaving them unrepaired can put stress on the oxygen sensors, reduce converter efficiency, and ultimately cause engine failures.

This table shows how much the cost might be for each additional repair or replacement:

What are some ways to lower catalytic converter replacement prices?

Replacing a catalytic converter is a major repair that can certainly break your budget, so we’ve laid out some tips to help you save money for this costly repair:

Address the check engine light immediately

Once you’ve noticed the check engine light on your car’s dashboard, don’t ignore it—act before it starts blinking. A flashing light indicates a severe problem, so seek immediate help from a mechanic. 

Ideally, choose a shop that can provide a diagnostic scan to help pinpoint whether it’s an easy fix rather than escalating to a full replacement. This preventive measure can help you save significantly on major jobs like catalytic converter replacement.

Choose direct-fit over universal converters (when possible)

While direct-fit converters cost more upfront, you’ll save money overall by choosing them over universal converters. Direct-fit converters are engineered for a specific vehicle make, model, and year. They come with all the necessary parts and accessories, making installation faster and reducing labour costs.

Choose an independent mechanic instead of a dealership

Car services at dealerships often cost more because they must cover higher overheads (facility costs, brand reputation, warranty coverage). This is why independent mechanics are more cost-effective: they can install OEM parts at lower labour rates, reducing your total cost without sacrificing quality.

Specialised exhaust shops may also handle catalytic converter work at competitive rates and often offer welding services if a universal converter is used (which dealerships may not).

What should you look for in a professional mechanic?

Catalytic converter removed during automotive exhaust system repair (Source: iStock)

Finding a reliable mechanic who can meet your specific needs and deliver quality work can be challenging. So, here’s a quick checklist of the things to look out for when choosing a mechanic.

Credentials and qualifications

While the UK doesn’t require licenses for auto technicians, it helps to check if they have formal qualifications like an IMI Level 3 Diploma in Light Vehicle Maintenance and Repair. This indicates they’ve passed rigorous standardised exams covering engine repair, brakes, electrical systems, and other automotive specialties.

Some mechanics also hold manufacturer-specific certifications from dealers, which show additional expertise with particular brands.

Specialisation and experience 

Beyond certifications, a good mechanic should specialise in your vehicle. Some independent shops focus on just one or two makes, such as all Toyotas and Mazdas, which gives them deep expertise unavailable at generalist shops. Others develop extensive experience in specific areas, such as transmission rebuilds or electrical diagnostics.

Evaluating their expertise and past work is important, since different vehicles have different issues. A mechanic familiar with your car’s common failure points can diagnose problems more quickly and accurately than someone encountering your model for the first time, potentially saving you from costly, unnecessary repairs.

Transparent pricing

A professional mechanic always provides a written estimate before starting work. This should break down the parts (with brand and model numbers), labour (usually the hourly rate multiplied by the estimated hours), and any additional fees. 

Warranty coverage

Ask the mechanic about warranty coverage. A reputable shop should cover both the parts installed and the technician’s workmanship. If the repair fails within the warranty period, the shop should fix it at no additional cost. Because this protection matters, always get the warranty in writing before work begins.

Cat converter issues making you grumpy? Get help on Airtasker

A catalytic converter replacement is a significant expense, but understanding what drives the cost can help you make a smart decision. The key is finding a trustworthy mechanic who can diagnose the problem correctly and provide transparent pricing. 

At Airtasker, you can easily connect with reliable car mechanics by posting a task. Simply describe the issues you’re experiencing and mention your budget and timeline. After posting, you’ll receive quotes from qualified Taskers in your area.

Don’t let a failed catalytic converter add to your stress. Find a reliable mechanic today with Airtasker.