How to book the cheapest flights possible

Tech and tools to save you airfare dollars

Airplane
You can find cheap flights on your phone—if you know where to look.Marcus Zymmer/Unsplash

Got your eye on a getaway? Ready to take off somewhere new? Thanks to the web and those pocket computers we call smartphones, booking a flight is easier than ever before. But, as seasoned campaigners will know, flight prices shift substantially based on timing and demand, which can sometimes leave you paying hundreds of dollars more than you need to. To make sure you're getting the best deal every time, you'll need to consider timing, and take advantage of the digital tools now at your disposal. Here's how to take to the skies for the lowest possible price.

Timing

If you buy a ticket the day before you need to fly, your deals will be much more limited than if you plan in advance. So what's the best time to start booking tickets? Peter Greenberg of CBS News suggests booking your trip between 45 and 60 days in advance, depending on where you're going, because airlines don't have the data to offer cheaper fares any earlier.

Hopper says Tuesdays and Thursdays are the best times for booking if you want cheap deals, but admits there's no one-size-fits-all formula.

But the day of the week that you book your tickets isn't as important as the day of the week you actually fly. Most people don't have a choice of travel times and are stuck booking flights over the weekend. So if you have the flexibility to go mid-week instead, you can save some cash. Another way to drive down prices is to avoid holiday periods and other busy travel times, if you can. It's also well worth checking for big events happening in the city you're flying to—you might be surprised at how much difference a big business conference can make to the price you'll have to pay. If you're prepared to do some waiting around at airports, you can save even more.

Flight comparison tools

As with insurance, hotels, and just about everything else you can buy online these days, there are a wealth of aggregator sites out there that will gladly compare flight prices for you. Expedia, Lastminute.com, Orbitz, Ebookers, Travelocity, Google Flights, Momondo, and more will happily scour the web for deals on your behalf.

The process is similar across the board—you tap in your starting point and destination, plus your dates of choice (if you have them), and the site spits out the cheapest possible options, together with a host of filtering tools. Google Flights has a particularly clever price graph showing price changes over time.

Google Flights

Google Flights

The Google Flights calendar shows you prices over timeDavid Nield/Popular Science

Although these tools make it easy to browse flights, be aware of potential pitfalls. Some tipsters hint that, when you search for the same flight multiple times, a travel site can recognize that it's your second time around and bump up the price. For that reason, they recommend that you conduct your searches in your browser's incognito mode, at least at first.

Whether or not this gets you a better deal, however, isn't certain. Your browser's private mode can certainly limit the ways that websites can track you, but checking prices from different computers and locations (at the houses of your travel buddies for example) is just as good an idea for comparing the lowest prices.

Choosing a flight comparison site

Which site will track down the best deals? Unfortunately, there's no definitive answer. No single site wins out for every flight combination at every time of year from every location. But three sites have consistently earned our attention for their polish and comprehensiveness: Kayak, Skyscanner, and Hipmunk. As you would expect, all these sites have accompanying mobile apps.

Among the features we like in Kayak are the option to search based on budget rather than destination (see how far your money can take you), the way cheaper dates are automatically highlighted (based on historical data), and the ability to search other comparison sites at the same time. If you're flexible with your dates, you can view price information on a calendar to help you to find the best deal.

Skyscanner

Skyscanner

Skyscanner is one of several sites that will send low price alerts straight to your inbox.David Nield/Popular Science

Over at Skyscanner, you can also search for flights across a wide date range, with a simple traffic light color system directing you to the best deals. It offers slightly more comprehensive and flexible options than Kayak does, and it has a cleaner and smoother interface as well. You can also sign up for price alert emails that will let you know if there's a good deal on a route you've recently searched for.

Our third pick, Hipmunk, is another excellent choice for your flight-finding needs. As well as all the usual searching and filtering options, it has an "Agony" rating for its results—so you can see which flights will cause the most hassle in terms of changes and stopovers. The interface is a breeze to use, and sifting through the flights list is easier than on a lot of other sites.

It's definitely worth checking more than one of these flight comparison sites in your quest for the best prices. Often, different aggregators are better for certain routes than others. We'd also recommend checking directly with an airline or two, as they often keep some of the best deals for themselves to avoid paying search site commissions.

In addition to general flight comparison sites, take advantage of specialist sites. These track changing flight prices to help you get even better deals.

Take AirfareWatchdog, which will monitor the routes you request and let you know when the best deals for your chosen departure and destination points appear. Meanwhile Hopper, for Android and iOS, does the same job but in app form—you plug in your route and your dates, and Hopper tells you whether to buy now or hang tight. If you wait, you get an alert when your flight is the cheapest it's going to be (its makers claim a 95 percent level of accuracy, but it doesn't have data from all the airlines out there). Again, it's good practice to use these services in tandem—none of them promise to be infallible in predicting prices or getting the cheapest deals, but all of them can help in making sure you're saving as much money as you possibly can.

Hopper

Hopper

Hopper estimates whether it's best to buy now or waitDavid Nield/Popular Science

Lower-tech tips

On top of all the flight-scoring sites and apps out there, you can apply some tried-and-trusted tricks of the trade to avoid paying more than you need to. Searching for different airports in the same city, for example, can lead to reduced airfare. Bear in mind, however, that you're likely to be left with a longer train ride or a higher taxi fare to get to the main tourist sites.

Keep your eye on the small print too: If an airline gives you 24 hours to cancel a booking without any penalty, make the most of that extra day—keep monitoring prices to see if you can grab a better deal. We'd also suggest following airlines on social media (for as long as you can bear it), because they often advertise special offers and deals. Remember that airlines want your direct business if they can get it, and they'll often reward people for not going through a third party.

A host of factors affect flight prices, including supply and demand. On the most popular flights, getting a cheap deal may well be close to impossible, so adjust your expectations accordingly. If you travel the same route regularly, you should get a better sense of what's a good price and what isn't, which means you won't have to rely so much on third-party tools to help you out.