The rental car rebooking strategy that can save you money on every trip

Most people book a rental car and move on. I treat that reservation as a rough draft.

After the reservation is made, I keep checking the price. In fact, it's not unusual for me to cancel and rebook the same rental car (or a different car) half a dozen times — sometimes even more — before my trip actually begins.

Rental car prices change constantly — the rate you see today might look very different a week or a month from now. That's exactly what makes this strategy work: because so many rentals allow free cancellation, you can book early as a placeholder and keep checking for something better.

My approach is pretty simple: I book a rental car as early as possible for each trip (usually through Expedia.com), but I specifically choose options that don’t require prepayment or at least offer free cancellation. Over time, I've found that many rental cars can be reserved without paying anything upfront, and they can usually be canceled for free up to 24 hours before pickup.

Because of that flexibility, I lock in a car that works for the trip and treat it as the starting point, not the final answer. I look for something with a reasonable price and the right pickup location, then I keep checking back periodically to see if anything changes.

And things change a lot. Inventory on Expedia fluctuates constantly, which means prices can drop or better vehicles can suddenly appear. Sometimes a larger car ends up costing the same as a compact, or a different rental company shows up with a lower rate than what I originally booked.

Over time those small adjustments can add up to meaningful savings — or a nicer (or bigger) car for the same price. That last part is important for my family of four, since we always have a ton of luggage with us.

If you want to try this strategy, here are a few moves that make it work:

• Look for free-cancellation cars on your favorite sites: On Expedia, Costco Travel, or any other of your favorite booking sites, filter or check for rentals that allow you to cancel without a penalty. These are the only cars worth using for this strategy.
• Book early, even if the price isn’t perfect: Reserve a car that works for your trip as soon as possible. Think of it as a placeholder that can be changed if better cars or prices come around.
• Check back regularly: Rental car inventory and prices fluctuate constantly. New cars, better rates, or larger vehicles can appear at any time.
• Be ready to rebook: If you see a better deal or a nicer car for the same price, cancel your original reservation and book the new one. Free cancellation makes this easy.
• Repeat as needed: You can do this multiple times leading up to your trip. Over time, these small adjustments often lead to significant savings or upgrades.

You can also use a site that lets you set up price alerts so you know when rates drop — sites like Kayak and AutoSlash are good for that. However, I prefer to check back manually so I can search for better, larger vehicles that fit my family of four and all of our bags.

Next time you book a rental car, set a reminder to check the price again in a week. Odds are, something better will be available.