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.

You can try to keep track of these various factors and refresh your searches regularly to monitor flight price trends yourself, or you can let KAYAK do most of the legwork for you.

1. When flights are cheapest in general

Even if you don’t know where you’re heading yet, you can still prepare to fly by understanding a few basics. In general, giving yourself at least 21 days’ notice to begin searching and purchasing a fare will maximize your ability to shop wisely. Flying to destinations during their off-peak seasons will also result in lower fares, and our City Guides can help you identify those key months by analyzing median airfare rates by month in various destinations you may be considering.

2. Choosing a destination based on cost

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.

Use the Explore map

When your point of origin is certain but your destination is open, peruse KAYAK Explore map. Enter your origin airport and you’ll rates will instantly populate across the map, identifying the cheapest flights to those locations. You can filter further by specific dates, date ranges, flight duration, budget, and more.

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.

Check the calendar

As you settle on your destination, it’s time to check the calendar, and we mean our calendar, not yours. Enter your airports on KAYAK Flight Search page and click the calendar icon to expand date selections.

Here you’ll find a calendar indicating the cheapest dates of that month to fly your desired route. You’re free to explore other months, as well.

3. Making your own cheaper route

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.

When entering airports on KAYAK, simply select “Add nearby airports” to include these in your search results.

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.

4. Waiting for the right moment

When you’ve determined where you’re beginning, where you’re ending, and even when you’re going, you’re still not beholden to a single advertised price. Rates will continue to change regularly but you don’t need to stress yourself out over when to take the plunge and book the tickets. Use KAYAK’s tools for expert guidance to buy at the optimal moment.

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.

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.

5. Harnessing 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.

How was this guide created?

An aeroplane lands on the runway in the early morning.

The short answer is through traveling! As a professional traveler in the sky every week, I take an average of 120 flights per year, so I’m well-versed in the art of finding the cheapest flight available when necessary. I’ve used years of this experience in partnership with KAYAK’s tools and teams of booking experts to prepare this cost-effective guide.

KAYAK offers a variety of Flight Filters to customize your search, and that includes a price filter to keep your budget in line. That’s not enough to determine the cheapest time to buy flights, though, so there are plenty more free tools to help you get there. Combining the following tools and top tips will help you find cheap flights for any route, so you can sit back and track your flight knowing you made the most cost-effective choice.

Getting started

Now that you’re armed with all the knowledge to score a flight at the best possible price, snag some travel inspiration with travel trends guide to clue you into today’s hottest destinations. And for even more savings, consider booking during slower travel months when costs for airfare and accommodations are typically reduced. When you’re ready to go, don’t forget to use KAYAK Trips to keep everything organized and ensure a seamless journey.

Some of our favorite cheap flight routes

This post is part of our Flight guide. Planning a trip but have questions about booking a flight? We get it. Find the answers in our comprehensive guide.

When are flights cheapest 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.

About the author

Brandon SchultzBrandon travels every week and makes friends with stray cats wherever he goes. Dogs, too... he once brought one home to the US from the Amalfi Coast. He’s written 6 books, visited 6 continents (still waiting on Antarctica), and would eat ice cream 6 times a day if he could. He lives in Brooklyn, New York, with his partner and three cats.

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