• Travel app Hopper's latest quarterly study says domestic airfares booked now for fall travel are 25% cheaper than they were in the spring.
• The average fare could drop as low as $289 roundtrip before rebounding in October and November.
• Good deals can be had from most major U.S. air hubs if booked by early September.

Would-be travelers looking to fly this fall may want to book their plane trips now, with travel app Hopper reporting that airfares are dropping this month from peak summertime prices.

"September and early October will be the cheapest times to travel, while August and early September will be the cheapest times to book travel for those months," said Hayley Berg, Hopper's lead economist.

The app's Late Summer (Q3) Travel Index claims that the average domestic airfare could drop as low as $286 roundtrip for bookings made in August. That's down 25% from May, when average fares topped $400, and is 3% lower than in August of last year.

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Airfares typically dip 10% to 15% in any given autumn as travel demand slows. "Offering lower airfare in August and September as travelers look to fall season travel is a seasonal occurrence, in line with the airlines' expectations for pricing throughout the year," said Berg.

But this year's drop is steeper than normal in the wake of abnormally high spring and summer fares that resulted from factors such as high jet fuel prices and greater-than-usual demand from a pandemic-weary public, she noted.

The average airfare for the rest of the year will remain at or below $300 if booked by the end of September before starting to rise again in October and November.

"We look at a weighted average price, so departures in the next two to three months will be weighted most heavily, [and] most travelers getting low prices in August will be traveling in September and October," said Berg, explaining how Hopper determines the best times to buy and fly.

Where to fly … and where to fly from

Travelers departing most significant U.S. air hubs should find good deals this month, according to Hopper.

"Many major airports are offering lower fares this fall compared to 2019 to major destinations," said Berg. "More than 200 to 300 destinations are priced lower this year from Chicago, Washington, D.C., Houston and Atlanta."

From New York, Hopper is seeing what Berg called great domestic deals. "We're seeing airfare to … top destinations as much as 27% lower than 2019 prices." Sample airfares from New York area airports include:

• Orlando, Florida for $151 ( down 7.3% versus 2019)
• Miami for $140 (down 27% versus 2019)
• Las Vegas for $253 (5% lower than 2019)

International flights from major U.S. hubs that are good value include:

• Washington, D.C., to Lisbon, Portugal, for $423
• Boston to Dublin, Ireland, for $452
• Washington, D.C., to Copenhagen, Denmark, for $518

Do good fares outweigh airport aggravation?

OK, airfares are more affordable. But do cheaper prices compensate for all the potential headaches travelers have been encountering when flying, such as flight cancellations or delays?

Berg said flight disruptions will remain a problem, despite temporarily improving last month. Delay rates, for example, had improved in July but then jumped back up to 25% from 18%.

Thus, many of the firm's customers are taking "proactive measures to safeguard against potential disruptions," she said, including the purchase of trip insurance products. In fact, 1 in 5 Hopper clients now opt for such protections when booking.