By far, the best airfare search tool I've ever used in the ITA Software Trip Planner. It's free to use, and no account is required. To use it for free, click "Log in as a guest" once you're at the login screen. What's so nice about this tool is that it lets you search a comprehensive list of airline fares and schedules from just about every airline worldwide. Plus, there are no ads and other annoying sales gimmicks; just the data you need to help you plan your trip. In fact, I think this tool is used by many travel agents.Once you find the flight that matches your schedule and price range, click "Show booking details" in the upper left. This will show you a booking code, and a price break down, among other things. To book the flight, you'll need to call the airline and tell the representative you want the rate associated with the correct booking code. The site will say something like "1 adult in booking code K, covered by fare (B1) below." So, when you call the representative all you need to tell them is the date, flight number, and the booking code to get the price shown on the ITA Travel site. On average, the ITA Travel search tool will find better rates than the actual airline sites (southwest.com, aa.com, united.com, etc.) themselves. Enjoy.
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