Illustration of a car being depicted as a piggy bank and a person putting coins in it

It’s not just the extra “drop-off charges” when you return a car to a location that's different from where you picked it up. Car-rental companies these days also charge fees for everything from gas to GPS to tolls.

That last one is particularly irksome, according to people who have written to Consumer Reports about hidden fees.

Consider the traveler in Texas who told us that every time he went through a highway toll, the car-rental company dinged him $15 on top of the toll price, leading to an extra $90 in “administrative fees.” “They will charge $15 to process even a 31 cent toll charge,” he says. “Completely ridiculous!”

When it comes to renting cars, "consumers have to be particularly diligent, as the price quoted rarely seems to bear any resemblance to the price charged when the car is returned at the end of a trip," says Anna Laitin, director of financial policy at Consumer Reports.

To make matters worse, Laitin says the car-rental companies sell add-ons and have fee structures that make it difficult to comparison shop or know what the final cost might be.

Here are some fees to watch for when renting cars, and how to avoid them. 

More on Rental Cars

Toll Transponders
Rental companies often charge extra for the privilege of using their transponder, the thing you stick on your window or dash that lets you pass quickly through tolls.

The fix: Before you opt for one, make sure you’ll be driving on toll roads. If you are, consider using Waze or Google Maps and click “avoid toll routes.” Or if you have a transponder on your car at home, check whether you can bring it with you and whether it will work where you’re traveling. Also ask whether the rental company will charge a separate fee for using it.

Prepaid Fuel
You’ll almost always pay a premium when you prepay for fuel.

The fix: Ask the car-rental staffer where the closest gas station is to your location, and plan for extra time to return with a full tank.

Facility Charges
Some rental companies pass along fees from the airport where you pick up your car, which can range from a few dollars to $10 or more a day. Some call it an “airport concession fee” or “concession recovery fee.”

The fix: Though it may not be convenient, you can avoid the fee—and sometimes get a lower rate overall—by renting from an office a few miles away from the airport.

Additional Insurance
This extra charge can often be avoided because your personal auto insurance or the credit card you use to pay for the rental may provide coverage.

Added Extras
Before opting for GPS, satellite radio, or another extra, check the cost—and make sure you really need that addition.

Editor's Note: This article also appeared in the July 2019 issue of Consumer Reports magazine.