Catalytic converter replacement cost
A catalytic converter replacement typically costs £250–£700 with a quality aftermarket cat at a UK independent, or £800–£1,800+ for a genuine OEM unit, which is often what stolen-cat victims on hybrids are quoted. Which one you need depends on the car.
What it costs
| Job | Typical UK price |
|---|---|
| Aftermarket type-approved cat, fitted | £250–£700 |
| OEM cat, fitted | £800–£1,800+ |
| Hybrid OEM cat (theft replacement) | £1,000–£1,800+ |
| Lambda/oxygen sensor at the same time | £90–£200 extra |
| Anti-theft cat cage/shield | £150–£400 |
Failed or just a sensor?
A P0420 "catalyst efficiency" code does not automatically mean a dead cat. Tired lambda sensors, misfires and air leaks can all trigger it. Replacing a £600 cat to cure a £120 sensor is a classic overcharge, insist on proper diagnosis first.
The legal bit
Any replacement cat must be type-approved for your specific car, and removing a cat entirely is an MOT failure and illegal for road use, whatever an online seller implies. Cheap universal cats that are not approved for your model can fail the MOT emissions test within a year.
If yours is stolen
It happens in minutes to high-clearance hybrids. Report it, go through insurance for OEM replacement where possible, and fit a cat shield or marking kit after. Parking against a wall or in busier spots genuinely reduces the risk of a repeat.
Common questions
How do I know if my catalytic converter has failed?
Sulphur or rotten-egg smell, loss of power, rattling from a broken internal core, failed MOT emissions, or a persistent P0420 code after sensors and misfires have been ruled out.
Will a cheap aftermarket cat pass the MOT?
A quality type-approved aftermarket cat, yes. Very cheap universal cats often cannot hold emissions in spec for long, especially on hybrids and low-emission engines, and fail within a year or two.
Why was my hybrid quoted so much more?
Hybrid cats carry a higher precious-metal load and are usually only available OEM, which is also why thieves target them.
Can I drive without a catalytic converter?
It will usually run, but it is illegal for road use, an automatic MOT failure and very loud. If yours was stolen, treat it as an insurance job rather than a reason to go without.