Finding the best deal on plane tickets can be a confusing, stressful process. There are so many websites that purport to be helpful, and so much conflicting advice about how to look and when to buy. To make it all easier on yourself, start here.
When to Shop
The first rule of searching for flights: Start looking as far in advance of your trip as possible. Last-minute price drops don't happen often enough for that to be a useful planning strategy, and you're also likely to make a better decision when you're not panicking. Try to book at least a month in advance for domestic flights, and at least two for international travel.
It's been a longstanding rumor that the best day to book a flight is Tuesday. There's some disagreement on that: According to by Expedia and the Airlines Reporting Corporation (ARC)—which counts most major airlines among its members—Sunday is actually the best day to book. Even if that's true, don't count on an extreme discount; , which does its own big study every year, notes that the average discrepancy between tickets day-to-day is something like 0.6 percent.
What the data shows to be much more important is the day of the week that you fly. Common sense is borne out here: Most people prefer to travel around weekends, so midweek flights are likely to be less expensive. That doesn't mean you can't find a reasonable flight leaving after work on a Friday, but if you're able to leave on a Tuesday instead you might get a better deal.
The way you handle your search then depends on whether you have a particular location you need to get to, or if you're just indulging some general wanderlust.
When You Want to Go Somewhere Specific
First, check flight comparison tools like Google Flights and Kayak. They're intuitive and will aggregate all available flights within the parameters you set. Both also have the option for you to see a comparison of flexible dates, to see if shifting your itinerary by a day or two would make a difference.
If you don't need to book right away, you can set up a fare alert and track prices over a couple weeks. Both Google Flights and Kayak will automatically send you emails when the flights you're looking at change price.
Make sure to check Southwest, too. It doesn't allow its data to be aggregated by Kayak or Google Flights, so you won't see their fares there.
Be Open to Multiple Legs…but Beware of Multiple Airlines
Flights with layovers tend to be cheaper than flying direct, and if you don't mind spending the extra time, it can be a good option. But booking through different carriers is a big gamble, especially for international flights: The last thing you want is for a delay in your flight from Kathmandu to Delhi to make you miss your flight from Delhi to London and then also your flight from London to D.C. If you don't show up for a leg on a different airline, the carrier has no obligation to rebook you gratis—so in that worst-case scenario, you're potentially looking at spending much more to get home than you saved through your original hustle.
Factor in the Other Costs
The search site displays flights so that, in addition to date, airport, and price, you can clearly see how different itineraries rank in terms of "Agony"—how many layovers and how long they are, which amenities (like Wi-Fi or meals) are offered, and so on, so that you can decide whether you're really saving anything at all.
Lifehack: Take a Connecting Flight, Then Don't Connect
Say you're trying to get from D.C. to Philadelphia, and for whatever reason, a direct flight is more expensive than a flight to Columbus, Ohio, that connects through Philadelphia. In that case, you can just book the lower fare, take the first leg of the trip, and get off in Philly. The website helps you find these tickets, which they call "hidden-city" fares.
The downsides: you can't check bags, since they'd continue on to the final stop without you; and you'd have to book departure and return separately. It's also not recommended for international travel, since some countries require you to show a valid visa for the flight's final destination before boarding in the States.
When You Want to Go Anywhere at All
These are great options if you're staunchly committed to low fares but aren't locked in on one destination. If you have the flexibility to book first and request time off later, so much the better.
Scott's Cheap Flights
This sends out email alerts when there are significant price drops, generally on international flights leaving from the U.S. It's free to sign up (well, free if you barter off a bit of your personal information). You can also pay to be a premium subscriber and get alerted to extra deals. Scott's will aggregate all the U.S. cities and carriers offering the deal, tell you how much more it would cost to check bags, and estimate how long they expect the fares to last (usually no more than a day or two).
If you jump on a too-good-to-be-true price and book it directly with the carrier, rather than through a third-party vendor, you still have a small grace period to make sure you can take the flight; requires airlines to give you 24 hours to cancel your ticket without penalty.
Newsletters from Bare-Bones Carriers
Sometimes you have to sit through a lot of chaff to get the wheat, the wheat here being plane tickets that don't cost an arm, a leg, and your sense of sanity. Surrender your email address to airlines that care less about the, ahem, niceties of travel, and you'll be getting plenty of alerts from them about deals! And steals!
It's going to feel a little spammy. But when Frontier has that $20 ticket from Cleveland to Palm Beach, you'll be the first to know.
One Last Tip: Use an Incognito Window