Fare timing · booking window calculator
When is the best time to book a flight?
How far ahead to book, by trip and by holiday, from Google's five years of Google Flights fares, checked against Expedia's and KAYAK's 2026 studies. Enter your date to see your own booking window.
Checked Nov 12, 2026By Steven MoHow we check Report a correction
When should I book my flight?
Windows from Google's analysis of five years of Google Flights fares (Oct 2026). They're averages across many routes: a sale or a deal can beat them on any day.
Quick answer
Book U.S. domestic flights 3 to 8 weeks ahead and international flights 1.5 to 4.5 months ahead. Google's five years of fare data puts the lowest average domestic fare 39 days before departure and the lowest international fare 89 days out. Holidays need more time: about 5 to 10 weeks for Christmas. The day of the week you book barely matters.
- U.S. domestic
- Lowest about 39 days out (range 22 to 57 days)
- International
- Lowest about 89 days out (range 50 to 133 days); little change inside it
- Europe
- Lowest about 90 days out; book at least 49 days ahead
- Mexico and the Caribbean
- Lowest about 43 days out (range 24 to 69 days)
- Thanksgiving
- Lowest about 34 days out; October is usually cheapest
- Christmas
- Lowest about 56 days out; best deals late October to mid-November
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How far in advance to book a flight
Days before departure when the average fare was lowest in Google's data, and the range where fares stay close to that low.
| Trip | Lowest average fare | Low-price range | In weeks or months |
|---|---|---|---|
| U.S. domestic | 39 days before | 22 to 57 days | 3 to 8 weeks |
| International | 89 days before | 50 to 133 days | 1.5 to 4.5 months |
| Europe | 90 days before | 49 days or more | 7 weeks or more |
| Mexico and the Caribbean | 43 days before | 24 to 69 days | 3 to 10 weeks |
| Thanksgiving | 34 days before | 21 to 57 days | 3 to 8 weeks |
| Christmas | 56 days before | 33 to 67 days | 5 to 10 weeks |
| Spring break (March and April trips) | 50 days before | 29 to 64 days | 4 to 9 weeks |
| Summer (July and August trips) | 21 days before | 20 to 47 days | 3 to 7 weeks |
Google's figures, published October 2026, average many routes over five years, so treat them as the odds, not a promise. A sale or a deal can beat them on any day.
Best time to book domestic flights
Book U.S. flights 3 to 8 weeks ahead. In Google's data the average domestic fare was lowest 39 days before departure and stayed close to it from 57 days out to 22. Inside three weeks it climbs. KAYAK's 2026 analysis of its users' searches lands in the same place: around 30 days ahead, with booking too early or at the last minute costing more.
Booking much earlier doesn't help on average: more than 57 days out, fares in Google's data were higher than inside the window. If you find a good fare early anyway, book it. Under U.S. rules, a ticket bought at least a week before departure can be cancelled without penalty within 24 hours (or held at that price for 24 hours, depending on the airline), so you have a day to keep looking.
Best time to book international flights
Most international trips
Lowest about 89 days out · range 50 to 133 days
Book 1.5 to 4.5 months ahead. Google found the lowest average fare 89 days out, but the drop across the whole 50-to-133-day range is small, so book as soon as you see a fare you like inside it.
Europe
Lowest about 90 days out · range 49 days or more
Book at least 49 days ahead. Fares were lowest about 90 days out, and Google says waiting rarely pays off: inside seven weeks, fares rise.
Mexico and the Caribbean
Lowest about 43 days out · range 24 to 69 days
Book 3 to 10 weeks ahead. These shorter trips behave more like domestic ones: lowest 43 days out, in a range from 69 to 24 days.
One study disagrees: KAYAK's searches found international fares lowest on average 1 to 2 weeks before departure. That's searched prices over 15 months rather than fares tracked over five years, and waiting that long risks the flights you want selling out, so we'd treat a late fare as a pleasant surprise rather than a plan.
When to book holiday flights
Holiday fares climb earlier and faster, so book sooner than for the same trip in a quiet week.
Thanksgiving
Lowest about 34 days out · range 21 to 57 days
Book 3 to 8 weeks ahead; Google says October is usually when Thanksgiving flights are cheapest. The busiest day to fly is the Sunday after Thanksgiving: TSA screened 3.13 million people on it in 2025.
Leaving Wed, Nov 25? Book between Sep 29, 2026 and Nov 4, 2026; the average low is around Oct 22, 2026.
Christmas and New Year
Lowest about 56 days out · range 33 to 67 days
Book 5 to 10 weeks ahead. In Google's 2026 data the best deals fell between late October and mid-November, five days earlier than the year before.
Leaving Sun, Dec 20? Book between Oct 14, 2026 and Nov 17, 2026; the average low is around Oct 25, 2026.
Spring break
Lowest about 50 days out · range 29 to 64 days
For March and April trips, book 4 to 9 weeks ahead. Google found the low point a full week earlier than the year before.
Leaving Sun, Mar 14? Book between Jan 9, 2027 and Feb 13, 2027; the average low is around Jan 23, 2027.
Summer
Lowest about 21 days out · range 20 to 47 days
For July and August trips within the U.S., Google found fares lowest just 21 days out, in a range of 20 to 47 days. Summer is the busiest season to fly, so on popular routes don't leave it later than that.
Leaving Thu, Jul 15? Book between May 29, 2027 and Jun 25, 2027; the average low is around Jun 24, 2027.
Which days you fly matters as much as when you book: Thanksgiving Day, Christmas Day and New Year's Day are among the quietest days of the year at U.S. airports. See the cheapest days to fly around the holidays
Best day of the week to book a flight
It barely matters. In Google's latest analysis, Wednesday edged out Tuesday as the cheapest day to buy, but buying on a Wednesday saved only about 1.4% compared with Sunday, the most expensive day. Expedia's 2026 report names Friday the cheapest day to book and Sunday the most expensive. KAYAK calls the old advice to buy on a Tuesday "simply not true".
The day you fly makes a much bigger difference: in Google's data, a Monday-to-Tuesday-or-Wednesday round trip cost about 14% less than a weekend one. The cheapest days to fly
| Study | Cheapest day to book | Priciest |
|---|---|---|
| Google (Oct 2026) | Wednesday, about 1.4% less | Sunday |
| Expedia (Feb 2026) | Friday | Sunday |
| KAYAK (Mar 2026) | No reliable day | Not reported |
Best time of day to book flights
There isn't one you can count on. Airlines change fares with supply and demand, and their pricing systems update them around the clock, sometimes several times a day. KAYAK says a price drop is about as likely at any time of day, on any day of the week. Book when you see a good fare in your window rather than waiting for a particular hour.
When do flight prices drop?
Not on a schedule. Fares move with supply and demand: they can drop when a flight is selling slower than the airline expected, when it runs a sale, or when a competitor cuts its price on the route. On average, though, the pattern is the one in the table above: fares ease into the low-price window and climb after it.
Coach fares on leisure routes are the ones that occasionally fall close to departure; business and first class usually go the other way, KAYAK notes. Waiting for a last-minute drop is a gamble that rarely pays on a route people want to fly.
- Track the priceGoogle Flights emails you when a tracked fare drops a lot, for set dates or for any dates over the next few months.
- Use the 24-hour ruleFor flights to, from or within the U.S. booked at least 7 days ahead, airlines must let you cancel within 24 hours without penalty or hold the fare for 24 hours.
- Get deal alertsWe watch fares from your home airport and email you when one falls well below its usual price, including the short-lived sales that never show up in averages. Get free alerts
Best time to book a flight FAQ
For U.S. domestic flights, 3 to 8 weeks before departure: Google's five years of fare data puts the lowest average fare 39 days out. For international flights, 1.5 to 4.5 months before (lowest around 89 days), and for Christmas 5 to 10 weeks before. A sale or deal can beat these averages on any day, so set a price alert too.
Sources
Figures checked against each study on Nov 12, 2026. These are averages across many routes and years. Your route can behave differently, so set a price alert as well as booking in the window.
- Google: Trends and tips for 2026 holiday travel (Oct 5, 2026), from five years of Google Flights data
- Google: Google Flights price tracking and the cheapest time to book (Aug 28, 2023)
- Expedia 2026 Air Hacks report: Friday takes off as the new cheapest day to depart and book
- KAYAK: The best time to book a flight & the cheapest days to fly (data updated Mar 26, 2026)
- U.S. DOT: the 24-hour reservation requirement (hold or cancel without penalty)
- TSA checkpoint travel numbers: people screened nationwide each day (Jan 1, 2025 to Nov 11, 2026)
Read how we collect and check this data, or tell us if something's out of date.
How we picked and checked these studies · Cheapest days to fly
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