There is no magic day to book flights: the day you buy changes the price by only a few percent. Expedia’s 2026 Air Hacks report found Friday was the cheapest day to book (about 3% less than Sunday), while Google’s analysis found Tuesday and Wednesday slightly cheaper, with only about a 1.4% difference between the best and worst days. What matters much more is the day you fly and how far ahead you book: midweek departures can be 8–14% cheaper than Sundays, and the best fares usually come about one to two months ahead for domestic flights and two to four months ahead for international trips.
Best day to book flights: what the data says
| Question | Expedia 2026 Air Hacks | Google flight data (2026) |
|---|---|---|
| Cheapest day to book | Friday (about 3% cheaper than Sunday); Saturday for US domestic | Tuesday and Wednesday (about 1.4% difference) |
| Most expensive day to book | Sunday (Monday for US domestic) | Sunday |
| Cheapest day to fly | Friday overall (about 8% cheaper than Sunday); Tuesday for US domestic | Leaving Monday and returning Tuesday or Wednesday (about 14% cheaper than weekend trips) |
| Best time to book domestic | 15–30 days ahead (about $130 less than 6+ months ahead) | About 39 days ahead (range 22–57) |
| Best time to book international | Booking 6+ months ahead was the most expensive | About 89 days ahead (range 50–133) |
| Cheapest month to fly | August overall; January for US domestic | Not stated |
Is Tuesday the best day to book flights?
Not really. The idea that airlines release cheap fares on Tuesday afternoons dates from a time when fares were loaded manually. Today, airlines change prices continuously using automated revenue-management systems, and fares can drop on any day. Google’s data does show Tuesday and Wednesday as marginally cheaper days to book, while Expedia’s shows Friday; either way, the saving is only a few dollars on a typical ticket. Book when you find a good fare, rather than waiting for a particular day.
What is the cheapest day to fly?
The day you depart has a far bigger effect than the day you book. Sunday is consistently the most expensive day to fly, because of weekend leisure and business travel. Expedia found that, for US domestic flights, Tuesday was the cheapest and least busy day, and Friday was about 8% cheaper than Sunday across all its flights. Google found that leaving on a Monday and returning on a Tuesday or Wednesday saved about 14% compared with flying at the weekend, and up to 20% on domestic routes compared with Sunday. On many international routes, Tuesday and Wednesday are also cheaper than Friday and Saturday; for example, on flights from the US to Thailand, Tuesday departures have averaged about 9% less than Saturday ones.
How far in advance should you book flights?
- Domestic flights: about one to two months ahead. Google’s data puts the cheapest point around 39 days before departure; Expedia’s around 15–30 days.
- International flights: about two to four months ahead. Google found fares lowest around 89 days out on average, and around 90 days for Europe.
- Mexico and the Caribbean: around 43 days ahead.
- Holidays: earlier. Google’s figures suggest around 34 days ahead for Thanksgiving, 50 for spring break and 56 for Christmas, and the risk of booking late is higher at peak times.
Booking very early rarely pays off: Expedia found that tickets booked six months or more before departure cost more on average than those booked in the one-to-two-month window. Booking at the very last minute is usually expensive too, except for occasional unsold seats.
What is the cheapest month to fly?
In Expedia’s data, August was the cheapest month to fly overall, about 29% cheaper than December, and January was the cheapest month for US domestic flights, about 19% cheaper than December. December, around the holidays, is the most expensive month almost everywhere. The best month depends on your destination’s seasons: for example, the cheapest time to fly to Thailand is outside its December peak, while flights to Europe are cheapest from November to March, excluding Christmas.
Do flight prices go down at night or at 3 a.m.?
There is no reliable evidence that searching or booking at a particular time of night gets you a lower price. Fares change whenever seats sell or airlines adjust prices. Flying at unpopular times is different: early-morning and overnight flights are often cheaper than mid-afternoon and evening departures because fewer people want them.
Do flight prices go up if you search repeatedly?
There is no good evidence that airlines raise prices because you searched a route several times, and browsing in private mode does not unlock cheaper fares. Prices often change between searches simply because the cheapest seats sold or the fare was updated. Price alerts are a better way to track a route than repeated manual searches.
More ways to find cheaper flights
- Be flexible with dates. Use the calendar or price graph view on Google Flights, Kayak or Skyscanner to see a whole month.
- Set price alerts as soon as you know your trip, then book when the price drops into the normal range.
- Consider connections. Google found nonstop flights averaged about 20% more than flights with a stop.
- Compare nearby airports. Expedia found airports such as Fort Lauderdale, Las Vegas and Orlando around 25% cheaper than the US average.
- Count the extras. On budget airlines, baggage and seat fees can wipe out a low fare; see our guide to budget airline baggage allowances in Southeast Asia.
- Fly into the cheapest gateway. For Europe, see the cheapest airports to fly into Europe.
- Use the 24-hour rule. For flights to or from the US, most airlines let you cancel within 24 hours of booking without penalty if you booked at least a week before departure, so you can lock in a fare and keep looking.
FAQ
What day of the week do flight prices go down?
There is no fixed day. Studies show small differences, with Friday (Expedia) or Tuesday and Wednesday (Google) slightly cheaper for booking, but prices change every day.
Is it cheaper to book flights on a weekend?
Sunday has been the most expensive day to book in both Expedia’s and Google’s data. Expedia found Saturday the cheapest day to book US domestic flights, but the differences are small.
Is it cheaper to book flights last minute?
Usually not. Last-minute fares are typically higher than fares booked one to three months ahead, especially on popular routes and in peak season.
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