Before booking any trip, one of the first questions most travelers ask is how much the flight will cost, but there’s rarely just one answer to that question.
A number of factors influence the cost of plane tickets and they often change, so understanding some of these indicators is essential for booking when flights are cheapest. To help you determine the best days to book flights, I’ve analyzed KAYAK’s data on both one-way and round-trip flights, both domestic and international.
The findings reveal that while there isn’t a single best day to book, certain days consistently offer lower average fares. In many cases, having a flexible schedule can lead to significant savings. Here’s a look at which days to fly, so you can plan your vacation accordingly.
Which days to fly?
If you’re planning to fly domestically you may find the most advantageous prices by leaving on a Friday and returning on a Tuesday. Doing a full week from Tuesday to Tuesday also works. If you’re planning to go abroad, a Thursday-to-Monday trip might offer you the average lowest airfare.
If going to Europe for three days is a little too short, though, a Wednesday-to-Wednesday trip appears to be the top overall deal with the lowest overall average. These are far from the only days for which you’ll find great deals, though. Here’s the breakdown of all the data.
When to fly domestically?
KAYAK’s data found that the average lowest domestic airfares are on Wednesday, with one-way fares averaging $193. Tuesday was a close second with an average of $195 for one-way fares. Monday, Thursday, and Saturday were next with fares in the $215 to $216 range.
Not surprisingly, Friday and Sunday were the most expensive at around $224 and $238, respectively. So, if you can get on a plane midweek, it may prove to be a lot more cost effective.
How to save when flying on a Friday within the U.S.?
If you do want to fly domestically on a Friday, you may be best served buying a round-trip flight. KAYAK’s data found that Friday and Wednesday had better deals when flying round trip, with an average ticket price of $342.
Tuesday was slightly more expensive at $345, followed by Thursday’s average price of $351. Sunday and Monday were the most expensive, costing about $395 and $374 for departures, respectively.
The lowest average fares for domestic return flights
The lowest average fare for return flights was found on Tuesday, at $331, followed by Monday and Wednesday at $337 each. Sunday was the middle ground with return flights averaging $357. Friday was the most expensive day for returns with average ticket prices of $387, with Saturday being slightly better in terms of airfares at $370 and Thursday at $368.
So, according to KAYAK’s data, a Friday-to-Tuesday long weekend round-trip flight may be the lowest-cost option if you can swing it.
When to travel internationally?
International flights followed a similar trajectory to that of domestic flights, with a few small differences. Tuesday seemed to offer the best deal across borders with an average one-way ticket price of $673, followed closely by Monday at $682.
Midweek flying continued to be, on average, more cost-effective than flying on the weekend with Wednesday showing the next most affordable one-way flights at $691. Next was Sunday at $692 and then Thursday at $722. Friday’s $753 one-way average was the most expensive.
When to leave for an international round-trip flight?
Round-trip international flights seem to have a flatter price trend, though some days are still a little less expensive than others. Thursday has the average lowest fares for departure, where ticket prices averaged $993. Wednesday was next at $1003, followed by Tuesday departures at $1012.
The most expensive day to depart on an international round-trip flight was Saturday at $1037, so you’ll see that the difference between lowest cost and most expensive is only $44, or less than five percent of the total ticket price.
When to return from an international round-trip flight?
Return flights on international round trips had a much larger price variation, though. Monday had the lowest return airfares, with average prices around $963. Tuesday is next lowest with an average of $975.
Prices climb steadily as the week goes on, with Wednesday ($1013), Thursday ($1040), Friday ($1062), and Saturday ($1070) bringing higher average prices. Average return airfares seem to dip back down a bit on Sunday, with average international ticket prices at $1015.
What does all of this mean?
Well, none of it is exact science, as airfares go up and down for all kinds of reasons, and KAYAK’s data is merely a reflection of overall trends. That being said, no matter when you fly, KAYAK is always a trusted resource as the world’s leading travel search engine, checking thousands of flights to find you the top deals for you.
So even if your travel plans don’t always allow you to book on days with the lowest airfares, KAYAK can help you find a fare that’s affordable for you, whether you’re looking to explore the U.S. or see the rest of the world. Read the tips to below to score lower fares.
Tips for finding low airfares
If you’re traveling for vacation rather than for a function that requires you to be in a specific location, you have the flexibility to shop around for destinations with cheaper flights. Here are some tools KAYAK offers to help you narrow down your best choices with finance in mind.
1. Use the Explore map
2. Get there quicker with KAYAK Direct
If layovers stress you out or you simply want to minimize your total travel time, you may want to fly somewhere that has direct flight options from your point of origin. Good news: You don’t have to overpay just to avoid layovers.
Use KAYAK Direct to enter your preferred origin airport and you’ll receive a list of direct flight destinations sorted by flight time. Select “Show routes on map” at the top of the list and you’ll return to the KAYAK Explore map with these routes illustrated by price.
3. Check the calendar
4. Make your own cheaper route
When entering airports on KAYAK, simply select “Add nearby airports” to include these in your search results. Sure, you can’t set the prices of flights yourself, but there are some things you can do to bring fares down by getting a little creative. First, consider branching out to other airports in your area, including regional airports.
If your airports are firm, check out our Hacker Fares to search combined one-way tickets on multiple airlines that may be cheaper than advertised round trips from a single airline. If one airline won’t offer a cheap enough price for you, perhaps you’ll find your target price by mixing and matching among various competitors.
5. Look into KAYAK’s crystal ball
Once you’ve selected the airport and date parameters that best fit your needs, we’ll tell you if it’s a good time to buy. The Price Forecast model analyzes user trends to assess demand for your route and let you know if we think prices will go up or down for this flight over the next 30 days.
It’s not a guarantee, but it’s based on scads of data that are excellent predictors of upcoming demand, which is what drives most fare costs. Just take a look at the “Our Advice” box above the flight filters on the left to find our recommendation.
6. Set alerts for cheaper fares
If you have time to wait for cheaper flight prices than what you’re currently finding, we can keep an eye on it for you. Set a Price Alert for the flight parameters you’re searching and we’ll let you know if the price goes down. You can do this by selecting “Track prices” in the “Our Advice” box mentioned above, by “hearting” a search result you want to track, or by manually setting an alert in your KAYAK user profile.
7. Harness the power of competition
While airlines would always prefer you book through them directly, you may find cheaper alternatives through booking partners. KAYAK simultaneously searches hundreds of travel sites that include both booking partners and the airlines themselves and provides all of them in your search results, giving you the transparency, you need in order to determine who’s offering the best deal.
Once you make your choice, we’ll redirect you to that provider so you can make your purchase securely.
Best time to book flights FAQ
Every airline’s goal is to get the most money possible for each seat sold, which means airfare pricing is one of the purest examples of supply and demand in action. To do this, popular leisure routes and cabins (economy) are priced high further in advance, which is when vacation travelers tend to book. These seats tend to go down over time as the airline seeks to fill the plane before take-off. Business routes and cabins (business/first) are priced lower upfront to fill minimum quotas, then hiked over time as short-notice corporate travelers scramble to get a remaining seat.
The oft-repeated idea that it’s cheaper to purchase airfare on Tuesdays is simply not true. We analyzed airline price trends every day of the week and busted this myth with the discovery that observing demand trends over time was far more important than booking on a specific day of the week. Watch this video to learn more.
The cheapest days to fly are the days when others are not flying. Friday and Sunday are heavily traveled for weekend events and getaways, but Tuesday and Wednesday are the least traveled and, therefore, might be the cheapest.
As noted above, this is more common with economy class cabins and those routes considered to be leisure travel routes (i.e., vacation destinations). For business class and first class seats, or routes are heavily flown by corporate travelers, the reverse is more often true, with prices increasing as the departure date approaches.
The short answer here can be frustratingly unhelpful: Flight prices change as often as airlines want. As the flight fills or doesn’t fill, airlines will continuously change prices to maximize their potential profit, which means fares may not only change daily but can even multiple times throughout the day. Flight prices vary as well depending on the season, the seats you want to book and ultimately the balance between supply and demand of seats.
Sometimes. Airfare prices change regularly based on supply and demand, and the airline’s resulting prediction of how it can maximize income on remaining seats. Computer software is often in charge of analyzing this and updating fares. This can certainly happen at night, but it is equally like to happen any time of day, any day of the week.
This blog post was originally published on June 26, 2023, and updated on August 26, 2024.
