Airline ticket prices vary dramatically, making it hard to know whether you’re getting a good deal on your flight or getting taken for a ride.
A new analysis by Hopper shows that the most expensive economy class ticket on a plane can be as much as six times the price of the cheapest seat on the same flight.
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The site compared prices for flights from Los Angeles to San Francisco and found that while most people spent less than $300, some scored seats for less than $100 and an unlucky few spent more than $600.
The report says that the availability of deals depends on the airline, with Delta passengers seeing the least variation in prices ($150-$400) and passengers on Alaska Airlines seeing the most ($100-$600).
The variability of prices also depends on the airport, with flights to Washington, D.C., showing the most variability, and flights to Kahului, Hawaii, showing the least. That means it’s more important for passengers flying to D.C. to compare prices, since it’s more likely that they could find a deal.
Other airports with high variability in pricing include Chicago, Myrtle Beach, North Carolina, Oakland, California, and Los Angeles.
It matters when you shop for your tickets. Airlines begin sales on Mondays and Tuesdays, so by Tuesday afternoon you’ll have the most potential deals to choose from, according to FareCompare.com. Tuesdays, Wednesday and Saturdays are typically the cheapest days to fly.