How to Use The ExpertFlyer Flight Availability Tool

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Yesterday I walked us through using ExpertFlyer to find award availability, but I also use the service to give me a sense of availability of fare classes on certain flights – for paid seats (not awards). There are a litany of reasons why a frequent flyer might want to know this information, including helping to understand upgrade chances, same-day confirm options and oversold flight possibilities (among many others). I always recommend arming yourself with information so you don’t have to rely on flaky phone reps or gate agents. There have been numerous times that I’ve been told “no options exist to re-route you” after a flight cancellation. I never trust that answer until I load up ExpertFlyer and see for myself. Nine times out of ten I can find my own routing that has open space and generally as long as there is space available, agents can put you on that flight. Each airline has it’s own quirks, but generally speaking ExpertFlyer gives as good a picture of flight loads as any non-employee is going to get.

Results for each flight will be a string of seemingly nonsensical information at first. It will read as a bunch of letters followed by a single number. The letter represents the fare class and the number is how many seats in that fare class the airline is willing to sell at the moment. However, a key thing to note is that fare classes are very complex – for example deeply discounted coach fares may require a Saturday night stay, so just because you see it available, it doesn’t necessarily mean you can purchase it. Fare classes are also generally arranged in order of high to low – so generally they start with F for full fare first class and go to the most restricted coach fare, which varies by airline. If you are a frequent flyer, I recommend familiarizing yourself with your airline’s fare classes, which can be done on the main ExpertFlyer homepage if you click the bottom left Reference -> Class codes. See below for Delta’s. You can always also click on a fare class in the search results and it’ll show you a short description.

Let’s pretend we are flying from JFK to Los Angeles tomorrow on Delta and we are currently booked on the noon flight which lands at 3pm. However, we want to get to Los Angeles earlier to enjoy a day at the beach. Changing your flight at the last minute can cost thousands of dollars, but luckily Delta allows changes on your day of departure for $50 (free for Gold, Platinum and Diamond medallions) – you simply have to call at exactly 3 hours before the flight you want to take and they will confirm you in your class of service if there is at least 1 seat available for sale in the full-fare coach bucket Y or F for first. Yes, you can check to see if they are selling seats, but you won’t get a good sense of whether the flight is close to being sold out since most seatmaps are generally all full – even if there are a bunch of seats available (since a lot of seats are held for gate assignment). And since you have to call 3 hours in advance and you know the flight is already sold out, you may want to start thinking about alternate plans.
Enter in your airport codes JFK to LAX on your dates and make sure to note your airline or else you’ll get a ton of irrelevant results. Then search – it’s that simple.
The results paint a pretty bleak picture. Not only is the 9am flight sold out, but the alternate routing through Salt Lake is also Y 0. At this point, I’d start checking other routings through other hubs like Atlanta, Detroit, Minneapolis, Cincinnati and Memphis. Nothing is showing up as available, so as a Diamond Medallion, I’m allowed to use co-terminals, which means I can depart from Newark or LaGuardia instead. This is where I find an eligible routing –  LGA-ATL-LAX – which would get me in at 12:10pm. I’d have to wait until exactly 3 hours before the LGA flight departs, so I’d be on the phone with Delta at 4am sharp to take that last remaining seat (if it was still there at 4am).
I usually pull up my flights on ExpertFlyer before I head to the airport to see if the flight could be oversold. Generally if there is availability in the cheaper fare classes, then odds are the flight won’t be oversold, but nothing is ever final until you get to the airport. In many cases, prior flights can be oversold and all of the sudden every single seat that day is zeroed out – that’s the risk with same-day changes, nothing is ever final until the rep can confirm you in a seat.

There are many more features of ExpertFlyer that I’ll be covering in the next couple of days. It gets a bit complex, so please comment below if you are lost and I’ll do my best to answer. If you want to try out ExpertFlyer, you can sign up for a 5 day free trial.

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