Crunches 917 Million Airfares to Reveal the Best and Worst Times to Book Flights

Annual Airfare Study arms travelers with best data to help them find the cheapest flights

CALABASAS, CA (March 21, 2018) – today published its annual Airfare Study, which analyzed 917 million airfares to reveal the best and worst times to buy airline tickets. On average, the best deals on domestic flights are available 70 days before takeoff versus 54 days last year. CheapAir found that the lowest fare for a given trip changes an average of 62 times during the 11 months that most flights are on sale. Each change averages $36, up or down.

Given this volatility, the study concludes that travelers are best to monitor airfares most closely during a booking sweet spot that has coined the “Prime Booking Window”. This year, the Prime Booking Window extends from three weeks to four months from departure date.

“We hear from travelers all the time who are frustrated that a fare they saw one day is dramatically higher the next,” said Jeff Klee, CEO of “And it’s equally disturbing when you book a trip and find out two weeks later that the price has gone way down. Our Airfare Study aims to explain the ‘method to the madness’ and give travelers a sense of the best time to buy and fly.”

In total, took an exhaustive look at 917 million fares from nearly 3 million individual trips in 8,000 markets to figure out how prices change over time. The analysis identified six Booking Zones that predict what travelers are likely to pay:

First Dibs: 169 to 319 days (in advance). Get the biggest selection but pay $50 more per airline ticket on average.

Peace of Mind: 122 to 168 days. Lock in dates with a good selection but pay a $20 premium on average.

Prime Booking Window: 21 to 121 days. Usually the best time to buy. Fares bounce around but frequently are available for within 5% of the lowest price.

Push Your Luck: 14 to 20 days. If you’re lucky, you might still find a good deal but, in general, fares rise, and flights sell out. Don’t try this around the holidays.

Playing with Fire: 7 to 13 days. Pay an average of $35 more than the First Dibs crew, and $85 more than the Prime Booking Window. Deals are a long shot.

Hail Mary: 0 to 6 days. Pay an average of $208 more than during the Prime Booking Window. Ouch!

Travelers can use’s When to Buy Flights Widget to find the specific Prime Booking Window for a particular route.

The study also debunks the myth that it’s better to buy a flight on certain days of the week, finding that the average fares purchased each day were virtually identical. On the other hand, the data clearly indicates that the day of the week to travel on is an extremely important factor, with an average fare difference of $76 between the least expensive travel day (Wednesday) and the most expensive (Sunday).

The time of year you fly is also very important. found that the Prime Booking Window changes seasonally as follows:

Summer: 14 to 160 days (in advance). Best Fare: 47 days.

Fall: 21 to 100 days. Best Fare: 69 days.

Winter: 21 to 110 days. Best Fare: 62 days.

Spring: 46 to 122 days. Best Fare: 90 days.’s study was careful to note that in reporting on the “average” best time to buy, the huge dataset tends to smooth out the curve, but in reality fares for any specific trip are extremely volatile, with changes every 5 or 6 days, even within the optimal “Prime Booking Window”. To further assist travelers in navigating this volatility, is the only site that offers Price Drop Payback™, which reimburses customers with a travel voucher up to $100 per ticket if their fare drops before the trip. also offers monthly payments as an option at checkout, which is great for more expensive or last-minute trips.

For additional information and data, visit the blog.

About CheapAir ®
Headquartered in Calabasas, CA,® and its team of over 100 travel enthusiasts use cutting edge technology, a boatload of airfare data, and superior customer service to make it easier and less stressful to buy affordable airline tickets. Our proprietary airfare shopping engine uses a patented algorithm that scours the web for the best deals and the most comfortable flights, and we show fares and flight options in a simple, easy to navigate display that includes which flights have which in-flight amenities. We offer monthly payments so you can Fly Now and Pay Later™, and Price Drop Payback™, which reimburses you with a travel voucher up to $100 per ticket if the fare drops before the trip. For expert travel advice, deals and inspiration connect with CheapAir on Facebook and CheapAir on Twitter.

CEO Jeff Klee started CheapAir in 1989 from his college dorm room after getting a crash course in the airline industry from planning his own backpacking trip through Europe on a student’s budget. still takes a creative approach to fare finding and, including its corporate travel services arm, Amtrav, has now helped over three million people buy plane tickets with confidence.