Over the last year or two I’ve done my fair share of flying and have refined my methodology of making sure that I always get the cheapest airfare available. I wish I could tell you “use this one service,” but in reality it doesn’t work that way. Since there are so many variables at play, you have to run searches at a number of sites. So how do you get the best airfare

Aggregators:

Independent:

Southwest

Booking Engines:

Major Airlines:

International:

There are basically three types of airfare websites: 1. Aggregators (ex: Kayak) that check airfares for many different airlines. They do not charge a fee but instead rely on affiliate hotel deals and on-site advertising like Adsense to make their money. These are historically the best bets. 2. Traditional booking engines (ex: Orbitz) that check multiple websites and take a small fee ~$6 in addition to the price of the flight. They process the sale on behalf of the airline and keep the fee. 3. Airline’s own websites (ex: JetBlue). If you find a flight on booking engines, check the airline’s own site so see if you can get it for the same price minus the booking fee. The important subset of this are airlines who do not play nice and do not offer their fares up to aggregators (ex: Southwest). You have to check their sites individually.

In my experience there is no ONE website that you can use to get the lowest airfare every single time. It fluctuates quite a bit because there a LOT of variables involved. Don’t ask me why – it’s just how it is.

My recommendation to get lowest airfare:

Start with Kayak, Farechase, Sidestep, Farecast.
Search Southwest and Jet Blue.
Check the old-schoolers: Travelocity, Orbitz, Expedia.
For good measure (and to be sure) check Cheaptickets, Hotwire, Priceline, Mobissimo, and Trabber.

You can also dig deeper using the quick list on the right. Try different days if you can (one day before/after), nearby airports (usually there’s a checkbox for that), and also check out building the flight with one-ways instead of round trip. This works especially if you have a 3-way flight or find that Southwest has a great 1-way price, but not roundtrip – then you can just use the other engines to get a cheap 1-way flight back.

If you feel really ambitious, check the airline’s own websites – list on the right (sometimes they’ll have unpublished deals).

When you find the cheapest flight that suits your needs, go ahead and book it. One of the things you’ll eventually run into is “oops, that $280 flight is now $320? messages. It will annoy the hell out of you. But that’s just how it is. You might want to check the other aggregators – sometimes you can catch what you just missed on and one and find it on the other.

Since travel is a big industry, there are a lot of shady websites/clubs/etc. that try to get your email address or try to get you subscribed to some service. I’ve never found those very useful for actually finding cheap flighs. The only exception is TravelZoo. I’ve signed up for their weekly Top 20 Travel deals email and I can say I’ve seen some impressive deals there.

Note: The above is mostly for US flights. If you’re looking for International, check out skyscanner.net, momondo.com, and trabber.com (non US). I haven’t tried them myself but I hear they’re good.

Feel free to share your flight booking strategies in the comments or give some travel tips of your own.

Best Sites for Cheap Flights : Tips for Finding the Lowest Airfare

Update: To always have the latest airfare strategies at your fingertips, bookmark this guide to cheap flights: Tips to Find Cheap Airfare.

Domestic Flights

1. Start with these airfare aggregators: Kayak, Farechase, Sidestep, and Farecast. Each one searches multiple airlines, but they tend to return slightly different results. They're usually best bets for cheap flights. Farecast gives you a fare prediction (only accurate about 50-75% of the time).

2.
Check the traditional discount search engines: Cheaptickets, Orbitz, Expedia, Priceline, and Travelocity. These too will return different prices for different flights. Most charge a small booking fee (see tips on your right).

3. Check Southwest (they do not share prices with above sites). Also check JetBlue, Delta, and US Airways to see if they have any site-exclusive specials.

4. Book the cheapest flight you can find above that matches your criteria. (See additional tips on this page). Enjoy your flight!

International Flights

International fares are a bit more complicated, but here are some shortcuts:

1. Check Mobissimo, Skyscanner, and Do Hop

2. Check the discount search engines that offer international fares: Cheaptickets, Orbitz, Expedia, Priceline, and Travelocity.

3. Delta tends to return cheap airfare to international destinations. Since US Airways is part of the international Star Alliance, they also have many international airlines included in their search:

4. Check which airlines serve your destination country at WhichBudget.com and run searches on individual airline sites.

5. Optional: call a local travel agent to see if they can beat any of the fares you found online. Sometimes travel agents will have access to international deals that are not available online.

Travel Deals

If you are a frequent flyer or are often looking for great deals on travel, there are a few good services that let you subscribe and get updates on current travel deals.

Many airfare websites mentioned above offer personalized travel deal updates by email and/or RSS, often by airport or favorite destination. Results are sometimes mixed and are often based on your location - many are nothing more than an automated flight price updates (and not necessarily "cheap travel deals").

Travelzoo Top 20 is a weekly email alert that includes some of the best handpicked travel deals available during any given week. Often these offers sell out fast, so it's a good idea to subscribe and check your email every Wednesday.

Sidestep allows you to subscribe to either domestic or international flight deals via RSS. They also have a Toolbar that you can download to automatically get notified about travel deals, but we have not tested this feature - user reviews are generally mixed about whether or not the toolbar is useful.

After running a search on Orbitz, you can signup for a service that will notify you once a flight that meets your target price becomes available. While in practice it doesn't always perform as well as in theory, it's still a pretty good option if you have some time to book your flight and are willing to wait.

"Southwest Ding!" is a downloadable application that places an icon in your taskbar and notifies you of special travel deals by playing a "Ding" sound anytime a special flight deal is released (usually for a limited time). Much like the Sidestep toolbar, some people find it useful while others find it rather annoying. Results tend to vary according to your location.

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