Plan too far ahead in some cities, and you could find yourself paying significantly more than if you would have procrastinated. In other places, waiting until the last minute may backfire spectacularly. “If you’re headed to a vacation getaway destination, those hotel rooms start to get very expensive last-minute,” says Adit Damodaran, an in-house economist at Hopper.com, a predictive flight and hotel pricing app. Meanwhile, big cities such as New York and San Francisco often have more rooms than they do visitors, making it possible to score a deal even as you drive into town.

Where to Delay Booking

In the two weeks leading up to check-in, nightly hotel rates decline an average of 13 percent in big cities, including Boston, New York, San Francisco, and Chicago. “There’s a much larger supply of hotel rooms,” Damodaran explains. “If they’re not filled by the weekend, hotels will offer last-minute deals.” For example, in Chicago, you can expect to pay an average of $150 a night if you book 40 days out. Wait until the week before a trip, and that figure drops to around $125 a night. In Boston, booking six months early can mean paying more than $250 a night. Book a week ahead of travel, and expect to face a more reasonable $150-per-night bill. In New York, early birds booking six months ahead can expect to pay almost $100 a night more than their procrastinating counterparts who wait until the days leading up to a trip.

Where to Book Early

Since Miami is among the most popular destinations in the U.S., Hopper recommends that travelers book hotel rooms two to three months in advance. If you’re heading to Miami before then, Damodaran suggests looking for options further from the beach. “You’ll find better availability and better prices inland,” he said. Still, even a last-minute hotel room in Miami—a city with a large volume and variety of hotels—will set you back less than a last-minute booking in Sedona, Arizona. “It’s such a popular leisure destination with a very limited supply,” Damodaran says of the gorgeous desert town. “Those hotel rooms get booked up really quickly because of low inventory, so prices are much higher for last-minute bookings.” Travelers booking a room within a week of their arrival in Sedona should expect to spend about $400 a night, based on Hopper’s data. That’s more than the approximately $300 a night average price for a last-minute hotel booking in Miami. For travelers struggling to commit to a room months ahead of a trip, Hopper recently introduced a price freeze service that allows travelers to pay a fee to guarantee specific rates for future bookings.

Where to Look if You’re a Last-Minute Traveler

Timely deals surface regularly in Orlando and Las Vegas, says Damodaran. And even at the very last minute, the average nightly hotel rate in Las Vegas is under $150, according to Hopper’s data. In Orlando, you can expect to spend about $100 a night for a last-minute hotel booking.