A Rental Car Puzzle

Photo Credit: Jeffrey Beall via Compfight cc

Have you ever noticed that whenever you rent a car, when they give you the keys to the vehicle, there are always two sets of keys?  But the two sets of keys are attached to the same key chain, and no matter how hard I’ve tried, I have never figured out a way to detach one set of keys from the other.

What could possibly be the point of giving customers two sets of keys that can’t be separated?  The downside is that if the keys get lost, two sets of keys are gone.  Also, the keys are much bulkier in my pocket than otherwise would be the case.

The only possible explanation I can see is that since no one carries around two attached sets of keys to the vehicle they own, people are less likely to confuse their own car keys with those of the rental vehicle.  It just doesn’t seem like that could be the logic, however.

So can anyone explain to me the real reason rental car companies do this?


Here's my guess: All new cars come from the manufacturer with two sets of keys. It's not worthwhile for the car rental company to store the second key in some central location in case the first gets lost or damaged, as the costs of storage, management and shipping would outweigh the cost of replacement. Thus, they give renters both sets in case one key (or FOB) breaks.


got this answer from a guy that works at a car rental:
"The reason is because the rental car companies keep the cars in their fleet for less than a year and then they are sent to auction. When they are sent to auction, they are required to have two keys and two remotes with the vehicle. If they don't have the two keys and two remotes then the rental car company is charged for a new key and a new remote. This will cost them over $125 per vehicle.

Since the rental car companies deal in tens of thousands of cars, the only easy way from them to keep up with the exact key and exact remote for a particular vehicle is to put the two keys and two remotes on the nondetachable key ring so they will not come apart and get lost.

So the real answer is that they don't have a better place to keep the extra key and remote and still be able to turn in two keys and two remotes when the car goes to auction."


Michael Larsen

When you take delivery of a new vehicle it comes with two sets of keys. When the rental companies remarket the cars its done (generally) close to its last drop location as is economically possible (auctions bearing significantly better results are sought out and if transporting the vehicles to said auction will bear a better price they will do so). Because nearly all companies interchange local and one way fleets the keys have to be portable and travel with the vehicles.

When wholesalers purchase there is a deduction for missing equipment (spare tires etc...) so the rental companies affix both keys to a braided cable that's nearly impossible to break. The rental companies remarket hundreds of thousands of vehicles a year so even a marginal deduction from the price would result in a very measurable loss.

Forrest Smith

My best guess is that often a car is not returned to the same location as it was originally rented. So if you pick up a car in Seattle, and drop it off in Portland, both sets of keys are with the car. If they only gave you one set, and kept the other, then they'd have to pay shipping costs of moving the keys to a new location, and ancillary costs of keeping track of two sets of keys which might be separated by hundreds of miles.

As to why you can't separate them, I would chalk that up to preventing them from becoming separated or lost by the driver, which would require the rental company to keep track of two separate keys. That being said, if you really did want to separate them, most wire cutters will cut through the keychain they give you.

Shehzad H

The cost for a key replacement is $200. If you lose the 2 keys that you can't separate, you owe the rental company $400. I don't know if that's to scare the consumer into not forgetting the keys ever, or to just capitalize on someone's mistake.

Jason Petralia

I always assumed it was because cars come with two keys, and it was the only way to ensure the keys stay with the vehicle. With the prevalence of one-way car renting it would be useless to keep the second key at the rental location, and costly to keep a national or regional key depository.

A main source of revenue for these companies is the resale of the car, and customers expect to receive both keys when they buy a car.

Michael Larsen

yikes, sorry for the duplicates.


So you can be sure no one else has an extra key for the car and you can feel safe.

Prateek Jain

I don't work for a car rental company, so by no means an authority on this subject. My curiosity propelled by your blog post, made me search for it on the web. Most people say it is for the convenience of car rental companies. When they send the cars to auctions/sale, they have both the keys/remotes in one place and do not have to search for them [1].

My cynical side makes me wonder if they charge you for both the keys if you loose the bunch?

[1] Source: Results which show up on Google.


So they don't lose the second set. If you separated the keys, you might as well throw the second set in the trash can, because that's how they'd likely end up. It seems simple, but I worked for a small car rental agency and we would have had trouble keeping track of them, so it would be a nightmare for a large location with a huge fleet.

Plus, cars are transferred all around all the time. When they're really separated from "home" the different locations will sometimes just transfer ownership of the vehicles to square up, so keeping the keys connected ensures that the second key stays with the car for eventual resale.

Also, never buy a former rental car, you would not believe the abuse those things receive!


So all of the keys assigned to that particular car always remain with the vehicle. When the car is sold, there is less confusion.

Don Carpenter

They do it just in case you return the car to a different location, so that location has everything that goes with the car.


I don't know for sure, but I would imagine that with most national brands (Hertz, Avis, ect) that offer the ability to drop off the car at a location other than where it was rented, it ensures that the keys stay with the vehicle. However, I would just put the spare key in the glove box or something like that.


I was wondering the same thing last week when I had rented a car and was faced with the same dilemma... what to do right? First I thought, they must separate right? Why have two sets - one key chain? So, I called the rental car company and they answered the dilemma by explaining, "that is just how it is." And, interesting fact, you are not permitted to separate the keys!!! No one tells you that, but its a fact of life, and that is just how it is.

Joseph Fairey

I am in the car business and have recently seen where most new models feature key fobs that can be programmed to other cars that share the same key platform. Most rental cars we get from auction have only one fob and we are constanly buying fobs from Ebay. (most still cost $100+) Our reasoning is that the empolyees that have access to key fobs will take an extra fob home and sell it for extra cash. By keeping them together and attaching them with a metal ring that is extremely hard to break, it creates a situation where employees either have to steal both fobs (which is much harder to do discretely since the company would then have no fobs) or not take them at all.


I believe it is for one way rentals. They want to make sure the keys travel with the car. I'd guess it also minimizes the amount of times a set goes missing since they can't be separated.


I just noticed this the last time I rented a car, too. My thought was maybe if the remote lock on one of the keys go out, you have a backup?


That has not been my experience.