There are an overwhelming number of websites and other ways you can book a flight. In this article we'll try to sort it all out and give you the best "insider" tips and tricks for finding the best deals. Figuring it all out may take a little effort, but the pay-off is worth it.
You may already know that booking your hostel with Hostelz.com's price comparison features is the cheapest way to find a place to stay, but here's how you can also save money on your flight. This is a simple step-by-step guide to everything you need to do to get the cheapest airfare possible.
When you're planning an overseas vacation, often your travel dates and destination are flexible, and you just want to know how you can get to Europe, southeast Asia, or some other general area for the lowest price possible. Currently there is just one way to do that, and it's one of the best "insider" tools available for researching flights. That tool is the website Matrix Airfare Search from ITA Software.
ITA is a software company (now owned by Google) that actually powers many of the flight booking sites like Orbitz, Kayak, HipMunk, and others. Because ITA is a software company, not a booking website, you can't actually book tickets on their site. But they do make the Matrix tool available for anyone to use to research flights, and it's extremely powerful. For example, using the "nearby" link when choosing your departure and destination, you can tell it to search for the cheapest flights from any airport within 100 miles of you, to any airport within 1000 miles of Paris. You can select "See calendar of lowest fares" to then see the lowest date the travel on. This is extremely useful for finding out when and where to fly to.
There is a belief that it's always cheaper to book your flight as early as possible to get the best price. This is often no longer the case. Prices for overseas flights are usually more expensive if you book too far in advance, and prices gradually come down, but then eventually spike upwards again as the travel date nears. The sweet spot for the lowest rates for international flights are typically 5-6 months before your departure date. For example, for peak season (summer) travel to Europe, the sweet spot to find the lowest fares is typically around February through April. But you'll usually still find rates that are nearly as low any time from 8 months before your flight up until about 2 months before. For domestic flights, the cheapest prices are typically 2-3 months before the departure date.
But if you're wanting to book a flight for a trip that is only a short time away, don't despair. There are often cheap tickets available for flights that haven't filled up in the last month or so before departure. But your options may be limited. You may need to fly to a city that isn't your primary destination and then take a short-haul flight or train, so check all of the possibilities with the ITA Matrix (see above) to find the best options.
Update: A new Wallstreet Journal article reports that you may find slightly lower fares if you make your booking on a weekend. Airlines make their lowest fares available on weekends for pleasure travelers, but keep the prices a little higher on weekdays when business travelers are more likely to be booking flights. But the difference is small, so if you're ready to make your booking today, it's probably not really worth waiting until the weekend.
What about being an "air courier" to fly for free/cheap? You may have heard stories about this online. You used to be able to volunteer as an air courier to get free or cheap flights overseas by carrying packages and documents for courier companies. But sadly, this type of courier business has been replaced by regular express mail in recent years, and this is no longer an available option.
Currently your best option for flying for free or reduced fair is using credit card miles, and it's easier than you may think. Many credit cards offer bonus points just for signing up. If you use a point-earning credit card for your daily purchases, most people are able to earn enough points for a free or reduced cost flight overseas every couple years or so. As long as you pay off your credit card balance in full every month, there's no reason not to use one of these cards to earn free air travel.
Our current favorite travel rewards card is the same one you'll see recommended by many travel experts, the Chase Sapphire Preferred Card. They give you a large sign-up bonus, and after that it's easy to earn points and use them to book flights. But a huge advantage of this card is that it's designed for use while you travel also. It has no foreign transactions fees (which is rare), and the card has a chip embedded in it, which makes it more useful in Europe where chip cards are often required (well, it's "chip-and-signature", which isn't as useful as "chip-and-pin", but it's still better than only having a magnetic stripe card).
If you're using credit card miles as described above, you'll use the credit card's rewards website to book your flight. But if you aren't using reward miles, you can book it anywhere. There are quite a few flight booking websites, but mostly you'll find their prices tend to be similar or often identical.
One exception is GetGoing. They offer an unusual "pick two, get one" deal where you pick two different cities you would want to fly to, and they don't tell you which one you actually got until after you book it. It sounds strange, but it's a technique for airlines to weed out business travelers and to give pleasure travelers lower rates. In some cases you can save 20% or so off what you would pay anywhere else for the same flight.
Update: Unfortunately GetGoing is no longer in business.
Aside from that, Kayak is a good starting point. It lets you easily find the cheapest price among the booking sites (similar to what Hostelz.com does for finding the best hostel booking price). Another one that may be worth trying is Skyscanner, especially if you are flying shorter routes such as between European countries.
We'll be updating this article over time, and we welcome your suggestions. Enjoy your trip!