In the first three installments in this series we looked at which airfare site is the cheapest, which site is easiest to use for a simple ticket purchase, and which is best if you have a flexible schedule. Now we’ll put it all together and see which is the winner when judging the best all-around airfare site.

Lessons from the three tests
Perhaps this shouldn’t have been a surprise, but we did learn that no savvy traveler should book a trip with only one gun in his or her holster. Of the seven sites we tested, five scored really well in at least one of the trials. It's a matter of figuring out which are best for the trip you are going to book, and then comparing results of at least two of them so you can buy your ticket with confidence. In some cases, using the wrong booking site will cost you around $5.00 per ticket and a bit extra hassle, but our price tests proved that sometimes the stakes are much higher than that.

Strengths and weaknesses of each

The worst
We can’t really recommend these two at all for buying airline tickets alone. They both offer good hotel plus air packages, and they offer many other services, but when you want to find the cheapest airfare without wasting time, they are not a good choice.

Expedia
Strengths – Expedia’s domestic flight search features work well on flexible dates.

Weaknesses – The site’s relentless attempts to up-sell the user into any manner of add-ons gets frustrating long before any ticket can be purchased. On top of that, they charge about $5.00 per ticket more than several other sites. It almost feels like they are trying to wear you down more than help you buy a ticket.

Travelocity
Strengths – If being slightly less aggravating than Expedia can be considered a strength, then that might be it.

Weaknesses – There isn’t anything Travelocity does particularly well compared to the others, and they also charge about a $5.00 premium per ticket for good measure. Not much to recommend.

BETTER
The following site stayed out of our basement group for a few key reasons.

Orbitz
Strengths – For the most part, Orbitz seems to be designed to make things easier for the user. The search functions work well and are easy to navigate. Even their attempt to add a hotel stay onto the ticket was easy to skip, but also done with an impressive search tool.

Weaknesses – Unfortunately, Orbitz does charge around $5.00 extra for most tickets. At least in this case, it feels like you might be getting something for your extra money, but knowing that we could skip to another site and book the exact same ticket for less money, means there isn’t much point going through the process.

BETTER STILL
This site proved in our tests that it could be very useful in certain situations.

Hotwire
Strengths – Compared to the above sites, Hotwire makes buying a ticket relatively simple and in some cases, they offered the same lowest price the sites below found. But their most useful feature is their flexible search function. They were the clear winner for searching whole months at a time, both for domestic and international flights. Their Hotwire Limited Rate offers (which don’t reveal the airline or flight times until after purchase) can be your best bet if your schedule is really flexible.

Weaknesses – For simple and specific searches, Hotwire frequently missed cheaper flights the others found in our tests. Unless you are searching flexible dates, their results seem far too erratic to trust.

THE BEST
These three sites could be considered two, since results from Kayak and SideStep are so similar, there’s no reason to bother trying them both.

Priceline
Strengths – Priceline was the clear winner in our price-alone test, although in most cases, the price was the same as the two sites below. On simple itineraries, they offered the same results as some others, but on our two complicated international itineraries, Priceline found a combination of cheaper flights that eluded the others. The site is relatively easy to use and the lowest price was always obtainable (unlike the two sites below). Consistently offering the lowest prices means this site deserves to be a key player for any cost-conscious traveler.

Weaknesses – At least as of now, Priceline doesn’t appear to offer any flexible-date searching. In some cases the site will mention how much you can save by going a day earlier or later, but since most budget travelers know that being flexible is one of the keys to saving on flights, we would really like a flexible dates feature to be added here.

Kayak and SideStep
These sites formally merged in late 2007, as of early 2008, they produced identical results in all our tests. We hear that plans are for them to establish different specialties in the future, so this is something we’ll keep an eye on.

Strengths – The twins found the lowest possible prices for all but the most complicated itineraries. They are easy to use once you familiarize yourself with their high-tech tools, and they usually get you from first click to your purchase in a short time with few headaches. Most people who spend time on these sites get hooked, easy to see why. They download all pertinent data they can find into your own browser-window database, and they allow you to filter the available flights many different ways to find your ideal tickets in only a few seconds. This is especially useful when flying popular routes with lots of competition, as sometimes a flight with a perfect time is a few dollars more than the lowest fare, a worthwhile alternative that stays hidden on most other sites.

Weaknesses – The true weakness is that these sites can only find you the best flight; they send you elsewhere to finalize your purchase. In some case, the site they refer you to doesn't offer the fare you want, which leads the user to a frustrating dead end. This happened more with some airlines than others; future software upgrades should fix this problem. The other downside to Kayak and SideStep is that their most powerful tools and features are not well suited to people who aren’t comfortable with database logic. In other words, someone who was unable to program the clock on their VCR (back in the days of VCRs), might struggle to learn the finer points of these modern airfare searching sites.

Conclusions
As mentioned above, there isn’t one site that is always the best to use. If the differences in price were never more than that $5.00 fee Expedia, Travelocity, Orbitz and (sometimes) Hotwire tack on, then you couldn’t be blamed for just accepting that and buying whatever ticket any site puts on top of its results screen. But sometimes, a better pair of flights is hidden or missing on one site and obvious on another, so this is a lot like going to two doctors or car repair places for a second opinion.

Which sites to use for these comparisons?
If you’ve looked at the results and you are someone who likes to get the best flights for your situation, purchase your tickets confidently knowing you didn’t miss something major, then you probably know how to approach this. It will depend on the specifics of your trip, but checking two sites should be enough in almost every situation. Once you learn how to use the Kayak/SideStep site, you’ll probably be hooked, and one of them will become your go-to airfare site, but you may want a second opinion before you type in your credit card number.

Final recommendations

• Check two sites before buying your tickets.
• Learn how to use Kayak or SideStep and always check one of them.
• If you don’t have much flexibility with dates, use Priceline for a second opinion.
• If you do have flexibility with dates, check Hotwire first. For a second opinion, consider their mysterious “Hotwire Limited Rate” offer if it works with your schedule.
• Once you are sure you have the best flights, buy the lowest price from the site you prefer.

Not looking for USA flights?  Use our international airfare search and compare our prices with the sites above.