Insurance Rate Guard Editorial Staff

OEM vs Aftermarket Parts: Avoid Costly Repair Gaps 2026

Disclaimer: Insurance Rate Guard is not an insurance agency and does not provide professional financial advice. Our content is for educational purposes only. Please consult a professional advisor before making any financial decisions.

An auto body technician holding a replacement fender panel up to a damaged car during a repair, illustrating OEM vs aftermarket parts in a car insurance claim.

After a crash, the body shop hands your insurer an estimate. Tucked inside that estimate is a quiet choice that decides part of your bill. It comes down to OEM vs aftermarket parts, and most drivers never notice it until the work is done.

OEM parts come from your car’s original maker. Aftermarket parts come from someone else. Your policy, your state, and your car’s age all shape which ones the insurer pays for. Get the choice wrong and you could owe the difference out of pocket.

Here is what car insurance covers, where your rights kick in, and when paying for original parts is worth it.

OEM vs Aftermarket Parts in Plain Terms

OEM stands for Original Equipment Manufacturer. These parts come straight from the company that built your car. Aftermarket parts, sometimes called generic or non-OEM crash parts, come from a third-party maker instead.

The Insurance Information Institute splits crash parts into those same two buckets: OEM parts supplied by the automaker, and generic parts from independent factories. Generic parts are “frequently produced in the same factory as the OEM parts,” per the III. They mostly cover the cosmetic outer “skin” of the car, like fenders, hoods, and door panels.

Used parts are a separate thing. Aftermarket parts are brand new, just from a different manufacturer. Progressive notes that used or recycled parts come off other vehicles, and your policy language decides whether those are allowed.

Knowing which of the three a shop plans to install is the first step to reading your estimate. For a wider walkthrough, see our guide on how to decode your auto insurance policy.

Why Insurers Reach for Aftermarket Parts First

Cost is the whole reason behind the OEM vs aftermarket parts gap. Generic crash parts run “26 to 50 percent less expensive than OEM parts and often have longer warranties,” according to III data. That price gap is large on a car full of body panels.

Insurers pass some of that savings to everyone. Progressive writes estimates with aftermarket parts because they “can return a vehicle to pre-loss condition and usually cost less than OEM parts,” which helps keep premiums down for all policyholders. Lower repair bills mean lower claim payouts, and that feeds back into rates.

The table below shows the basic trade-offs across the three part types.

PART TYPEWHO MAKES ITTYPICAL COSTNOTES
OEMYour car’s original makerHighestExact factory match; often required for newer or leased cars
Aftermarket (generic)Third-party manufacturer26% to 50% less than OEMNew parts; mostly cosmetic exterior panels
Used / recycledPulled from another vehicleLowestAllowed only if your policy permits it

Source: Insurance Information Institute and Progressive. Costs are general ranges, not a quote for your vehicle.

What Your Policy Pays For

That choice starts with your policy wording, which pays to return the car to pre-loss condition at the lowest reasonable cost. In practice, that often means aftermarket parts on the estimate. If you want only OEM parts, the coverage you bought matters.

Most insurers treat OEM-only repairs as an add-on. Progressive explains that “you generally need to have specific OEM parts coverage on your auto policy for your insurer to fully cover using only OEM parts.” Some carriers offer that add-on, often limited to newer cars. Progressive itself offers OEM parts coverage for motorcycles but not for cars, a reminder that availability varies by company and vehicle.

Without that coverage, the choice still exists, but the money shifts to you. If you or your shop pick OEM parts when an aftermarket part would restore the car, you “may have to pay the difference in cost between the aftermarket and OEM part,” per Progressive. On a single panel that gap can be small. Across a full repair it adds up fast.

Here is how the pay-the-difference rule plays out on a real claim. The shop writes an estimate with a generic fender, and the insurer approves that amount. You ask for the factory fender instead, so the shop reprices the job and bills you the gap before work begins. The policy still pays its share, and the upgrade is on you.

Some policies handle newer cars differently on their own. The III notes that a few policies “specify that only original equipment manufacturer parts must be used for repairs,” and others require OEM “only when repairing recent model cars.” Read your declarations page before the body shop starts so the bill holds no surprises.

Your Rights When Non-OEM Parts Show Up

You hold more leverage than the estimate suggests. An insurer “cannot require a policyholder to use only certain kinds of auto repair parts,” the III states plainly. The company can base its payment on the cheaper part, but the final call on what goes into your car is shaped by your policy and your state’s rules.

Disclosure is your biggest lever here. Many states make the shop or insurer tell you in writing when generic parts are on the estimate. The NAIC model regulation spells out the exact notice, which warns that the estimate uses parts “not made by the original manufacturer” and that those parts must be “at least equal in kind and quality in terms of fit, quality and performance.” Every aftermarket part also has to be clearly identified on the estimate.

Quality is not optional under that standard. The NAIC model bars an insurer from requiring aftermarket parts “unless the after market part is at least equal in kind and quality to the original part.” Parts made after the rule took effect must even carry permanent maker identification you can check.

Some states go further still. California, for example, bars insurers from requiring non-OEM crash parts unless the driver is advised in a written estimate before repairs begin, and each non-OEM part must be clearly identified by its manufacturer, per the California Department of Insurance. If you think a shop or insurer skipped that step, your state insurance department takes complaints.

How Part Choice Affects Safety, Resale, and Leases

The safety debate over aftermarket panels is mostly overblown. III data shows “these exterior generic parts do not compromise the safety of a vehicle.” The non-profit Certified Automotive Parts Association inspects generic parts and certifies the ones that meet its quality standards, so a CAPA-certified label is a useful signal.

Resale value is a common worry too. The III is direct here: using generic parts does not lower your car’s value. Diminished value can come from a serious collision history, but the III says a car “would not be diminished further in value by the use of generic parts.” If your vehicle is newer or expensive, that history still matters when you sell, which is one reason repair quality drives total cost on cars like a Tesla Model 3 or a Jeep Grand Cherokee.

Leased cars play by stricter rules. Lease agreements “clearly spell out what type of parts may or may not be used when a car is repaired,” the III notes, and many demand OEM. Skipping that requirement can trigger fees when you turn the car in. Our guide to leased car insurance requirements covers the rest of the fine print.

The OEM-Parts Endorsement and When It’s Worth It

An OEM-parts endorsement resolves the OEM vs aftermarket parts trade-off by telling your insurer to pay for original parts on covered repairs. It removes the pay-the-difference problem before it starts. Not every carrier sells it, and many cap it to cars under a set age, often around 10 years or newer.

The math favors the endorsement on a few specific cars. A newer vehicle still under warranty, a leased car with an OEM clause, or a model where panel fit affects safety sensors are the strongest cases. On those, the yearly cost of the add-on is usually small next to a single OEM repair bill.

On an older car the endorsement rarely pays off. Once a vehicle is past its prime, certified aftermarket panels restore it for far less, and resale already reflects the age. Match the coverage to the car, not the fear.

Before you buy the add-on, ask your insurer three things: which repairs it applies to, how old the car can be, and whether it covers structural parts or only cosmetic panels. Get the answers reflected on your declarations page, not just over the phone. A two-minute call now beats a surprise bill at the body shop later.

How to Save on Insurance

Smart choices in the OEM vs aftermarket parts decision, plus a tight policy, can cut both your repair bills and your premium. Five moves help the most:

  1. Read your declarations page before you ever file a claim, so you know whether OEM coverage is already included.
  2. Add an OEM-parts endorsement only on a newer, leased, or high-value car where original parts truly matter.
  3. Ask the shop for CAPA-certified aftermarket parts when generic parts are used, so quality is documented.
  4. Compare quotes every 12 months, since carriers price repair and parts coverage very differently.
  5. Raise your deductible on an older car and drop coverage you no longer need to free up premium each month.
  6. Get every non-OEM part identified in writing on the estimate, since most states require clear disclosure before repairs begin.

None of this takes long to check, but it saves you from a surprise parts bill after a crash. Look at your declarations page today, and decide now whether an OEM-parts endorsement fits your car. A few minutes of prep beats a fight with your insurer over a part you never expected to pay for.

Sources Used