Genuine, OE and aftermarket parts: what is the difference?

When you shop for a replacement part, you will see terms like genuine, OE and aftermarket. They are not always used the same way, but these are the usual meanings.

Genuine (vehicle manufacturer) parts

These are sold in the car maker's own branding, usually through its dealers. They are the same part the car was built with, and are often the most expensive option.

Original equipment supplier (OE or OES) parts

These are made by the company that supplied the part to the car maker, but sold under that company's own brand. In many cases it is the same part without the car maker's badge, often at a lower price.

Aftermarket parts

These are made by other manufacturers to fit and work like the original. Quality varies from budget to premium, so the brand matters.

What to check before you buy

• Choose a reputable brand. A well-known name is usually a safer bet than an unbranded part with no information.
• Look for approval markings. Replacement brake parts, for example, should carry an approval mark showing they meet ECE Regulation 90.
• Be more careful with safety parts. For brakes, steering and suspension, quality matters more than saving a few pounds.
• Ask about the warranty. A clear warranty is a sign the supplier stands behind the part.

For accessories and non-critical items, a budget option is often fine. For parts the car relies on to stop or steer, buy the best you can reasonably afford.