As summer approaches, travelers are preparing for trips in huge numbers after many people put off vacations for years during the COVID-19 pandemic -- and that's being reflected in the prices.

"This summer, Americans can expect to pay more for airfare than they have paid in the last 10 years," Hayley Berg, an economist at Hopper, an online booking platform, told "Good Morning America." "Right now, domestic round trip travel costs about $360, and that's up 15% versus 2019, the last normal year of travel before the pandemic, and up significantly since the start of the year."

But even though prices for travel are up amid the increased demand for travel, travelers can still get good deals, according to travel experts, who have a few key tips for locking in low airfare rates as summer travel heats up.

PHOTO: People wearing masks navigate through the domestic terminal of the Hartsfield-Jackson Atlanta International Airport in Atlanta, April 19, 2022.
Alyssa Pointer/Reuters
People wearing masks navigate through the domestic terminal of the Hartsfield-Jackson Atlanta International Airport in Atlanta, April 19, 2022.

Berg recommends customers book summer flights by the first week of May. After that, "prices will just continue to rise," Berg said.

"If you're planning a trip right now, be aggressive, start planning early and take a look at your route that you're flying and how busy it is," added Willis Orlando, senior product operations specialist for Scott's Cheap Flights.

Although you can wait for a sale or a day when fares have dropped on popular routes where there is a lot of competition, booking early is especially important if you are booking a trip in a region or route that does not have a lot of competition, Orlando told "GMA."

PHOTO: A sign stating that masks are required at San Francisco International Airport stands in a terminal after the federal mask mandate for airports and pubic transportation was lifted, April 19, 2022, in San Francisco.
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A sign stating that masks are required at San Francisco International Airport stands in a terminal after the federal mask mandate for airports and pubic transportation was lifted, April 19, 2022, in San Francisco.

"If your route is served by one or two airlines at most, you don't have that competition, you can expect these high prices to persist," Orlando said. "In that case, start monitoring it early, and as soon as you see a dip to a reasonable level, lock it in, because you're not likely to see a drop much further than that."

When shopping for airfare, flexibility in terms of dates and locations can mean better prices, whether that means leaving on a different day of the week or flying into a smaller, regional airport.

"Try booking your departing flight on a Tuesday or Wednesday, when prices are typically the lowest," Berg said. "Or if you're flexible on where you fly into or out of, check out more regional airports. Oftentimes, lower cost carriers will fly out of regional airports."

Another good way to get a good deal is to track prices for preferred flights.

"Use a price monitoring tool, so you're updated on where prices are and how they're changing," Berg said.

PHOTO: Passengers check in for flights at San Francisco International Airport, April 19, 2022, in San Francisco.
Justin Sullivan/Getty Images
Passengers check in for flights at San Francisco International Airport, April 19, 2022, in San Francisco.

Another concern that experts point to are pilot shortages, which have led to some airlines trimming summer flight schedules as well as delays and cancellations across the industry.

To avoid that, experts say to book on off-peak days and to book flights for the morning. If you're traveling for a wedding or other specific event, Berg recommends arriving a day or two early, in case there are delays or cancellations.

"The biggest thing you can do is be flexible and fly kind of off-peak, so if you're flying out of try flying on a Tuesday or Wednesday or Saturday. It is a little less busy those days, which means that if there is a problem somewhere, it's less likely to cascade into a kind of mass cancellation event," Orlando said.