The fare checker: Please fasten your seat belt . . .

Sunday, May 16, 2010

Airfares often appear to defy all logic. Traveling to the next state can cost more than flying across the country, flying out of an airport just a few miles away can save hundreds, and buying way in advance isn't always a sure way to cut costs. We looked for patterns by tracking a specific round-trip flight on a competitive route.

On April 7, we started tracking the round-trip economy airfare for United Flight 846, departing May 7 from Washington Dulles at 9 a.m. and arriving nonstop in Los Angeles at 11:35 a.m., with a return on May 10 aboard United Flight 856 departing Los Angeles at 10:47 a.m. and arriving nonstop at Dulles at 6:48 p.m. We checked the price at different times of day from different computers at both United.com and Bing.com/travel.

While our experiment is admittedly just a snapshot and not an extensive study, we looked for patterns or obvious reasons for price increases or decreases, including seat availability, competitor's sales and proximity to departure. Our conclusion: Pricing, at least on our flights, followed rhyme and reason, but was affected by multiple causes. A few more details about our methodology and observations:

-- A sale from a discount carrier affects pricing. We tracked a Virgin America sale of $299 round trip from Dulles to LAX that was active when we started looking at our United flights. Virgin offered the sale through April 24. While our specific flight pairing went to $373 11 days before the Virgin sale ended, United continued to offer other nonstops from Dulles to LAX for $299. On April 25, when Virgin raised its fare to $476, United's cheapest nonstop went to $486.

-- The number of seats available is not a determining factor for pricing until a difficult-to-discern tipping point is reached, and it could very well apply to only one leg of the trip. We deliberately chose flights served by aircraft of different sizes. We counted how many seats remained on each flight when checking the fare each day, and then looked at United fare prices for bigger jets with more available seats. The fare on our targeted flights permanently jumped from the starting point of $299 to $373 when 70 seats remained on the departing flight, and 20 seats on the return. For our control flights, the fare jumped when 70 seats remained in both directions.

-- As the date of departure grows closer, starting at about two weeks before travel, fares go up much more quickly than they do early in the process. Early on, fares are more likely to stay stable, or to even decrease for a day or two at a time. At the last minute, not unexpectedly, flights at odd hours with more open seats cost less. For example, on May 3, our targeted United flights were $1,013 round trip, but another United nonstop pairing, with 28 seats available on the red-eye return flight, was $455.

-- Carol Sottili

Chart: The fare checker

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