Cost to replace a catalytic converter

Thieves love catalytic converters because they contain valuable metals and are relatively easy to rip off a parked car. According to the National Insurance Crime Bureau, more than 52,000 catalytic converters were stolen in the United States in 2021 alone — a sharp increase from the less than 3,500 stolen in 2019.

However, catalytic converters may also just fail, especially when a vehicle is not maintained well or has mechanical issues.

Regardless of the reason your catalytic converter needs replacement, the price can vary quite a bit based on the make and model of your vehicle. That’s why we surveyed five mechanics from different regions of the U.S. to get real-world estimates for catalytic converter replacement costs.

If you want to learn more about catalytic converters, including how they work, what to do if yours is stolen, what the warning signs are when they’re failing and whether your warranty or insurance will cover a replacement, we’ve got you covered.

Key insights

• Catalytic converters are crucial in curbing vehicle emissions, and you probably can’t drive without one.
• Average estimates for replacing the catalytic converters in our sample vehicles ranged from $933 to $4,414.
• Comprehensive car insurance can help if your catalytic converter is stolen but not if it stops working — auto warranty coverage may help cover the costs to repair or replace one.

What is a catalytic converter?

First introduced in 1973, a catalytic converter (or “cat”) is a crucial component of a modern vehicle’s emissions control system. Cats reduce the release of specific pollutants (such as carbon monoxide, nitric oxide, nitrogen dioxide and hydrocarbons) by converting them into carbon dioxide or steam using rare earth metals (like platinum, rhodium or palladium).

The catalytic converter is typically under the car — usually right after the exhaust headers transition into the exhaust pipe. To find it, just look under your vehicle and trace backward from the exhaust tip toward the engine.

How does a catalytic converter work?

If you open up a catalytic converter, you’ll see what looks like a dense, honeycomb structure. This structure is made from heat-resistant ceramic, and it’s there to provide more surface area for exhaust gases to flow over. This honeycomb grid is also laced with precious metals, typically from the platinum family.

Each metal functions in a specific way:

• Reduction catalysts, like rhodium and platinum, react with nitrogen oxide by removing oxygen and breaking the molecular bonds into nitrogen and oxygen, which are harmless.
• Oxidation catalysts, like palladium and platinum (which handles both oxidation and reduction), change carbon monoxide into carbon dioxide by adding oxygen.

Once this happens, the resulting exhaust gases move out through the tailpipe into the air.

How much does it cost to replace a catalytic converter?

Replacing a catalytic converter can be expensive, which is why catalytic converter theft is so problematic. However, some catalytic converters cost much more to replace than others.

We got estimates from five different mechanics across the country to help you set expectations for what a catalytic converter replacement may cost you. We used three sample vehicles to represent different kinds of vehicles.

The Honda Civic, generally the most affordable of our sample vehicles, had by far the most expensive catalytic converter replacement costs in our survey. Meanwhile, the BMW 740i had the lowest average parts cost but a much higher labor cost than our other sample vehicles. The Ford F-150, one of the most popular vehicles in America, had the lowest average replacement costs by far.

In general, you can expect to pay more for an imported brand than a domestic brand, and you may pay much more for a vehicle like the Toyota Prius, which uses a special catalytic converter that’s incredibly valuable.

What to do if your catalytic converter is stolen

One of the telltale signs that your catalytic converter has been stolen is that your car is suddenly quite a bit noisier than normal. Because catalytic converters are placed before mufflers in most exhaust systems, your car will make significantly more noise now that there’s a gap in your exhaust system.

If you suspect your catalytic converter is gone, pop your head under your car near the front seats and look for any missing sections in your exhaust system.

If your catalytic converter has been stolen, you should get it replaced as soon as possible. Not only is driving without a catalytic converter loud, it’s often also illegal. If you have comprehensive car insurance, you should also call your insurer immediately. They can help you pay for your repairs and deal with other issues that may arise.

If you have comprehensive car insurance, you should also call your insurer immediately.”

Your best bet to replace the catalytic converter is to visit a respectable muffler shop or automotive repair facility. You can go to the dealer as well, but you may pay quite a bit more money.

Faulty catalytic converter symptoms

If your catalytic converter is still in place but you suspect that it’s not working properly, there are several signs you can look for to see if it’s faulty:

• Poor fuel efficiency: If a catalytic converter gets clogged, it can cause a backup of airflow coming out of the engine. This will lead to a drop in efficiency that you can see at the pump.
• Check engine light: One of the purposes of your vehicle's electronic control unit (ECU) is to monitor your vehicle’s systems. The ECU measures air-to-fuel ratios regularly, and if this ratio is out of whack, it triggers a check engine light. Although this is not a guarantee the catalytic converter is at fault, certain engine fault codes usually indicate a problem with the catalytic converter.
• Rotten egg smell: If a cat is clogged up or becomes damaged, the smell of rotten eggs can waft into your car. This happens due to the partial conversion of nasty pollutants, which manifests as sulfur dioxide.
• Poor performance: Due to a lack of exhaust gas movement, a clogged catalytic converter can have a major effect on performance. Since the exhaust gases must escape, the back pressure may cause your engine to stall or completely shut off.
• Failed emissions tests: Most people find out their catalytic converter has bit the dust when they fail their emissions test due to high levels of pollutants being emitted.

Catalytic converter repair costs

There are some situations where repairing your catalytic converter makes sense rather than outright replacing it. (Obviously, repair is not possible if your catalytic converter is missing.)

In the context of catalytic converters, "repair” usually means giving the cat a thorough cleaning to clear out any gunk that’s lingering on the inside. Repair is generally not practical if the damage goes beyond a clog, which means your catalytic converter likely needs to be replaced.

“Cleaning a cat may seem like a good idea to save a few bucks, but most of the time it ends up costing about as much to replace it with a new one,” said Jay Jindal, from Jindal-Andre Automotive Services in Washington, D.C. “Granted, some vehicles like Toyota and Honda have a much more expensive catalytic converter than brands like Ford. It’s best to weigh out the options.”

The repair process involves removing the catalytic converter from your vehicle and performing a thorough cleaning. Although the process of cleaning isn’t difficult, getting the catalytic converter off and on can be a challenge for those who are not mechanically inclined. This is especially true if it’s been on your vehicle for 10 or 15 years.

Getting a repair estimate ahead of time is difficult because a shop will not know how dirty the cat is until they remove it from the vehicle.”

If you can get away with repairing your catalytic converter, it can be a cheaper option than replacement. Repairs are billed by the hour at local labor rates. However, getting a repair estimate ahead of time is difficult because a shop will not know how dirty the cat is until they remove it from the vehicle. Also, don’t forget to figure out why your catalytic converter clogged up in the first place.

What if you have a warranty or insurance?

Whether you should contact your insurance provider or auto warranty provider for help paying for a catalytic converter repair or replacement depends on your situation.

If your catalytic converter was stolen

If your catalytic converter was stolen, check with your car insurance provider to see if you’re covered. Comprehensive car insurance should cover the cost of a catalytic converter replacement if it is stolen.

Just keep in mind that you may still need to pay your deductible, and some comprehensive policies require high out-of-pocket costs.

If your catalytic converter failed

If your catalytic converter broke down and your vehicle is under warranty, you may not need to pay to have it repaired or replaced. The Environmental Protection Agency mandates that automakers provide special warranties for emissions components, including catalytic converters. Under these warranties, major emissions components are covered for eight years or 80,000 miles, whichever happens first.

If your vehicle hasn’t been maintained properly, warranty coverage can be denied.

It’s worth pointing out that, should you find yourself outside of the manufacturer's warranty and the federal warranty limit, most extended car warranties will not cover your catalytic converter.

However, an extended warranty may cover whatever caused your catalytic converter to fail in the first place. For example, a blown head gasket can allow coolant to burn off in your engine, and that coolant can gunk up the catalytic converter. An extended warranty may not cover the cat, but it will help you fix that pesky leaking head gasket to stop the issue from recurring.

Terry, a ConsumerAffairs reviewer from Akron, Ohio, felt that their extended warranty was still worth it even after they had to pay out of pocket for their catalytic converter replacement: “After not receiving a discount on my catalytic converter failure, I was hesitant when my mechanic submitted the list of items that needed repaired on my Jeep. … Car Shield covered items that I didn't expect them to cover, including the rental car, front and back brakes, water pump assembly with everything that was associated, and saved me thousands of dollars.”

Bottom line

Replacing a defective or stolen catalytic converter can be an expensive problem to deal with if you’re not prepared for it. Personal loans can help if you need cash to pay for a repair now, and your vehicle’s insurance policy should provide coverage if your catalytic converter is stolen.

Although extended auto warranties generally don’t cover catalytic converters, they can cover the conditions that lead to their failure. Remember, replacing or repairing a catalytic converter is only one piece of the puzzle — catalytic converters rarely fail on their own.