OEM vs approved parts: what your policy decides

Somewhere between the accident and the repair, a question appears on the estimate that most drivers have never thought about: what kind of parts is the shop going to put on the car? The answer is usually not up to the shop, and not up to you. It's written into the policy you bought.

The three categories, in plain English

• OEM (Original Equipment Manufacturer). Made by or for the automaker, the same part the car left the factory with. Best fit, best finish, highest cost.
• Aftermarket. Made by an independent manufacturer to fit your model. Quality ranges from excellent to poor. Certified aftermarket parts have been tested by an independent body for fit and material.
• Recycled / LKQ ("Like Kind and Quality"). Genuine OEM parts taken from another vehicle of the same model. Original quality, already weathered, and often the practical choice for older cars.

Your policy is the one that decides

Most standard auto policies allow the insurer to specify aftermarket or recycled parts for repairs. Some policies include an OEM-parts endorsement, which requires original manufacturer parts. Others guarantee OEM only for the first few years of a car's life, then shift to aftermarket.

This is worth knowing before an accident, not after — it's one of the few line items on an insurance policy that visibly changes what your car is made of afterwards. If you drive something newer, leased, or expensive, ask your agent what your policy says about parts. It's often a small addition to the premium.

Where it genuinely matters

Not every part is worth arguing about. A recycled door shell from the same model year is the same steel the factory used. But there are places where the part choice is a safety and function question, not a cost question:

• Anything with a sensor in it. Bumper covers and mirrors on modern cars house radar and cameras. Fitment tolerances there are measured in millimetres, and a part that sits slightly differently can affect recalibration.
• Structural and crash components. Reinforcement bars and crush zones are engineered to deform in a specific sequence. That's a place to insist on tested parts.
• Aluminium and EV body panels. Fewer aftermarket options exist, and material matching matters more than it does on steel.
• Lighting. Headlight assemblies vary widely in output and sealing quality between manufacturers.

What a shop owes you here

Whatever the policy says, you should know what's going on the car before the work starts. A written estimate lists each part and its type. If you want an OEM part where your policy covers aftermarket, that's usually possible — you cover the difference, and you should be told the exact amount in advance, not discover it at pickup.

What shouldn't happen: a part type substituted quietly, or an estimate that doesn't say. The honest version of this conversation takes two minutes and saves everyone a difficult one later.

Two questions worth asking any shop

• "What does my policy actually cover on parts for this repair?" — a shop that bills insurers directly reads these policies every day and can tell you.
• "If I want OEM where the policy covers aftermarket, what's the difference in writing?"

Any shop that answers both clearly is a shop that will also tell you the truth about the rest of the repair.