Rethink how you buy airfare.

As we approach summer, airfares tend to rise, and this year is likely to be no exception. Travel research app Hopper[1] predicts that domestic flight prices will rise to about $229 round trip in April, from $218 in February — and up to $251 by June.

That makes it even more important that you’re smart about booking your flights. Unfortunately, many of us fall for some pervasive flight-booking myths. Here are four.

Myth 1: It’s almost always cheaper to have a layover.

Data released Monday from Hopper found that while, on average, you can save roughly 5% by choosing a flight with one stop, there are “an increasing number of non-stop flights available now that are cheaper” than those with a stop. Their research found that was true for about one in three flight queries.

“It comes down to who is competing in the market,” says Patrick Surry, Hopper’s chief data scientist. “For example, if the only nonstop option is a major legacy carrier, then other carriers will discount their options with stops to a lower price to compete for the business. But in a market where it’s a low-cost carrier that serves the nonstop, it can often be the case that options with stops (on major carriers) are more expensive.”

Myth 2: Booking on Tuesday is a sure way to score deals.

You’ve probably heard this “rule” before, but it’s one of the most pervasive flight myths out there. An analysis by flight deal site CheapAir[2] found that the average fares purchased were nearly identical on each day of the week, and Hopper found that Tuesday was the cheapest day to buy a flight for just 1.6% of domestic routes.

“While Tuesday historically was the day many airlines scheduled their sales — and competitors would match and compete that same day, into Wednesday morning — the explosion of tools through which people are getting information these days means any day can be an airfare sale day,” says Gabe Saglie, an anchor and producer at travel site Travelzoo. [3]

But that doesn’t mean timing doesn’t matter. Instead of focusing on which day to book, you may want to put more weight into the time of year and day of the week you depart. Wednesday tends to be the cheapest day to fly, the CheapAir analysis found, and January tends to have the best flight deals, followed by February; by summer, flight prices creep up significantly. Even better: Track prices for desired flights through a site like Google Flights GOOGL, +1.91%[4]   — this month, Google even launched a feature [5]where you can set a budget...

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