Guide
Catalytic Converter Replacement Cost
Cost drivers
What you pay comes down to a handful of factors. The biggest is whether you buy OEM or aftermarket, since the two can differ by more than a thousand dollars. How the cat attaches matters too: a unit welded into the exhaust takes far more labor than one that simply bolts in. Location plays a part as well, with a front cat tucked under the hood being more involved than a mid- or under-body cat. Finally, the engine itself drives the count, because a V6 or V8 usually runs multiple cats rather than one.
Cost ranges
| Type | Cost (USD) |
|---|---|
| Universal aftermarket cat | $150–$400 |
| Direct-fit aftermarket (legal grade) | $300–$700 |
| CARB-compliant aftermarket | $400–$900 |
| OEM (dealer) | $800–$2,500+ |
| Labor (1-3 hr typical) | $100–$400 |
Why aftermarket sometimes fails
Federal EPA aftermarket cats meet a lower precious-metal loading
than OEM. After 10,000 to 30,000 miles, they may no longer pass the
catalyst monitor, and P0420 returns.
CARB-compliant (California) aftermarket cats carry a higher precious-metal loading and tend to be much more reliable. They are required in California, but they are usually worth the extra money elsewhere too if you plan to keep the car for the long term.
OEM is the safest choice when
For some owners, OEM is simply the better bet. If you intend to keep the car five years or more, the longer service life usually justifies the price. The same is true where emissions inspections are required, since a cheaper cat that fails the catalyst monitor only sends you back to the shop. And if you have already replaced an aftermarket cat that failed, OEM is often the way to stop repeating the cycle.
Cat theft
Catalytic converters contain platinum, palladium, and rhodium, all increasingly valuable. Theft soared between 2021 and 2024.
Thieves tend to favor certain vehicles. The Toyota Prius is a frequent target thanks to its twin cats and lack of shielding, and the Honda Element is easy to get under because of its high ground clearance. Pickup trucks like the Ford F-Series and Chevy Silverado are common marks for the same reason.
You have several ways to push back. A cat shield, essentially a welded metal cage, runs $200 to $400. Some police departments will etch the VIN onto the cat free of charge, which makes a stolen unit harder to resell. Parking in a well-lit area or a garage helps, and comprehensive insurance covers most cat theft if the worst happens.
Don't just replace the cat without diagnosis
A failing cat is often a symptom rather than the disease. The trigger can be a bad O2 sensor, in which case the cat is actually fine and the alarm is false. It can come from running rich or lean, which poisons the cat but leaves the underlying fueling problem in place. A coolant leak can poison the cat as well.
Replacing the cat without addressing the root cause usually means the new one fails too, so diagnose the source before you spend the money.