How to book a flight without overpaying.

No single comparison site is always cheapest. In our test of nine routes, Google Flights, Kayak and Skyscanner each had the lowest fare on some routes and not on others. On most routes they were within a few percent, but on Singapore to Bali the priciest of the three was 42% above the cheapest. So unless a small saving doesn't matter to you, check your route on all three. Google Flights has the clearest calendar and price graph for scanning flexible dates. Kayak and Momondo are owned by the same company and show almost identical results, so there's no need to check both.

The exception is a reseller like Kiwi.com. It sells you the ticket itself rather than handing you off to the airline, usually a stitched-together self-transfer, and if you miss a connection, the next airline doesn't have to help. We keep it in the list only for contrast: it finished last on all nine routes. Stick to the comparison sites, then book direct with the airline.

None of the comparison sites sell you the ticket anyway. They find the flight and the price, then hand you to whoever's selling it. We search all three, then book straight with the airline wherever the price is close (Tip 3 explains why that's worth a few dollars).

The biggest factor in what you pay is how flexible you are. Use the whole-month and cheapest-month views to spot the cheap days, and check nearby airports on both ends. Check nearby destinations too: we regularly see Bali fares drop by a few hundred dollars just by flying into Kuala Lumpur first and booking a separate AirAsia hop onward. If you're genuinely open on where to go, put that to work: Skyscanner's Everywhere search and Google Flights' map both take one origin and no fixed destination, then rank the whole world by price, so a cheap fare can pick the trip for you. A midweek departure usually beats Friday or Sunday, and the awkward early-morning and red-eye slots are often the cheapest of the day.

Flexibility can also decide whether there's a direct flight at all. Not every airline flies every route every day, so a Monday-to-Friday trip might force a connection while Tuesday-to-Saturday has a nonstop on the exact same route. The quick way to see this without checking date by date: in Google Flights set the stops filter to Nonstop, then open the date grid. Any day with no direct grays out, so the whole month's nonstop pattern shows at a glance.

Online travel agencies (Trip.com, Gotogate, Kiwi, eDreams and the rest) often show a fare a few dollars under the airline. The catch is what happens when the airline changes your schedule, cancels, or you need a refund or a change: you can only deal with the agency, not the airline. Their support is often slower than dealing with the airline directly, because they've already been paid, and the airline will usually point you back to them.

When an OTA does make sense: a large price gap, or a mixed-airline itinerary no single airline sells. Otherwise pay the small premium, book direct, and keep the airline on the hook when it matters.

Layovers are usually cheaper, sometimes a lot. But don't just compare ticket prices: airport food, a possible overnight hotel, a transit visa, and the risk of a delay eating your connection all add to the total.

Then there's the self-transfer, the real trap here. Book two separate tickets, or an OTA "virtual" connection stitched together from different airlines, and those airlines don't know about each other. Miss the second flight because the first ran late, and nobody owes you a thing. A single ticket with a protected connection means the airline rebooks you for free when they cause the misconnect. On a self-transfer with under about 90 minutes to change planes, don't.

That unbeatable price is almost always the most stripped-out fare bucket. Basic Economy, or a budget airline's base fare, typically means no carry-on beyond a small personal item, no seat selection, no changes, and last to board. Add a bag and a seat and it can easily cost more than the normal economy fare you scrolled straight past. Add the bag before you compare, then look at the real total.

Chase value over the sticker price. A $520 fare with a bag and a protected connection beats a $470 self-transfer with neither. Compare the real total for the trip you'll actually take, not the teaser on the results page. The math matters most on the new long-haul budget airlines now flying intercontinental routes: a tempting base fare can land above a legacy carrier once you add a checked bag, a seat, and the ride in from a secondary airport.

The same stripped-out trick exists up front. A "Business Light" fare (Emirates, Qatar and others sell one) gets you the lie-flat seat and the full baggage. It drops lounge access, only lets you pick your seat at check-in, and adds change fees. Fine if all you want is the flat bed, worth knowing before you assume every business fare is the flexible one.

One last fare-bucket quirk catches groups and families: airlines price a multi-passenger search at the highest bucket that covers everyone. If two seats are left at the cheap fare and the rest sit a tier up, searching for four travelers quietly prices all four at the higher fare. Search as a single passenger to see the true cheapest fare, and when only a seat or two is left at that price, book those on their own rather than letting the whole group round up.

Airlines aren't interchangeable, and the gap compounds if you funnel your flying through one of them or its alliance (Star Alliance, Oneworld, SkyTeam). Miles add up toward free flights, seat selection, priority boarding and lounge access, and status earned on one alliance member is recognized across the others.

Signing up costs nothing and takes two minutes, so join before you fly even if you only fly once a year: the miles just sit in the account waiting. Some programs do expire them after 18 to 24 months of no activity, so a single flight or a card transaction every year or two keeps the balance alive. What isn't always worth it is paying more, or taking a worse routing, purely to chase status. Join everything, then let it break the tie when prices are close.

Return tickets aren't automatically cheaper. Price two one-way tickets on different airlines and they often come out lower, especially where budget carriers compete for the route, and they almost never cost more. You also get the flexibility to change one leg without torching the whole fare. The old warning that one-ways are punishingly expensive is mostly a US-legacy-carrier hangover now. Legacy long-haul is where it flips: on routes like the transatlantic a single return can still beat two singles, so check both rather than assuming.

See our test: we priced three trips as a return, then as two singles. Two one-ways won every time, by $45 on one route and loose change on another →

You don't have to leave from where you arrived. Fly into Bangkok and out of Singapore (an open-jaw) and skip a wasted backtracking flight. Google Flights and airline sites both do multi-city search. For a trip that hits several places, it's frequently cheaper than a simple return plus separate internal flights, and you see more of the region.

Airfares are filed market by market, in what's called the point of sale. The identical trip can be priced differently depending on which country's site and currency you buy it from. A weaker local currency and tougher home-market competition are what usually move it.

You don't touch your route or your dates. Keep Amsterdam→Bali exactly as it is, then re-price it with the search site set to another country and currency, usually the destination's, sometimes a third market. It takes 30 seconds and it's the same seats on the same planes. This is a genuine pricing difference, unlike the VPN tricks in Tip 10. Two catches: your card's country can limit which points of sale will take payment, and paying in a foreign currency brings its own card and conversion costs worth checking first.

Fares move on real supply and demand, not on your browser history. A VPN, incognito mode, clearing cookies, booking on a Tuesday or at midnight, hitting search one too many times: none of it changes the price. We've tested it, and so has everyone else. The cards below are the "hacks" that get shared the most and hold up the least.

The timing that does matter is how far ahead you book. The day of the week and the hour don't come into it. Roughly one to three months out for short-haul, two to six for long-haul. Don't leave it to the last minute, and don't book a year ahead either. Set a price alert and buy when it dips into a range you're happy with.

A couple of safety nets take the pressure off getting that timing perfect. On any flight touching the US, a Department of Transportation rule gives you a free 24-hour window to cancel most tickets booked at least seven days ahead, so you can grab a good price and sleep on it. And most US airlines have dropped change fees on everything above Basic Economy, so if the fare falls after you book you can often cancel and rebook at the lower price and take the difference as credit. Keep the alert running even after you've paid.

Two advanced tricks do sometimes work, with a catch. Hidden-city ticketing (booking A→C via B and getting off at B because it's cheaper) can work, but you can't check a bag, it only works one-way, and airlines can penalize your frequent-flyer account or cancel your return if you no-show a leg. Error fares (a genuinely mispriced ticket) are real and occasionally spectacular, but the airline can cancel them, so don't book non-refundable hotels around one until the ticket is actually issued: booked, paid, and confirmed by the airline, not just a booking-confirmation screen. Fly once a year? Skip both and stick to the tips above.