Warren Buffett said it, famously, best: Price is what you pay; value is what you get.
His words apply to buying airline tickets because low fares often come at a price. Here are some things to consider when you're hunting for a fare:
I've seen fares to Asia for hundreds less if you go by way of Atlanta, where the connection time is 34 minutes. A two-hour connection will cost more but is infinitely more sensible, especially when you consider that Atlanta consistently tops the traffic totals in the Airports Council International world report as the busiest in the world. It served 96.1 million passengers in 2014, the most current stats available.
Sometimes the connection on a low fare requires an overnight stay in Houston, Miami or Shanghai, at the passenger's expense. Sometimes this is a good thing if you think of it as "two cities for the price of one," and you actually want to spend 24 hours in a particular place. But if you don't have a cousin or friend to stay with for free, it can add considerably to your real cost.
Sometimes the lowest fares involve two or even three connections, so a nonstop flight might be more but a much better value. If you miss a connection, you might not continue your journey for hours or days later.
Time of day, time of week
The lowest fares are frequently only available on red-eye flights or 5 a.m. departures, perhaps from an airport that requires a long drive from home. To make the trip work, you might have to stay overnight at the airport before your departure.
The lowest fares are usually available for travel only on Tuesdays, Wednesdays and Saturdays. If that fits your schedule, great.
A $500 flight to Europe in winter is not the same thing as a $500 flight to Europe in the summer, if, indeed, you can find a fare that low. A low winter fare is not the same "value" as the same price in summer if great weather and more hours of daylight are part of the allure.
Airlines know that many passengers prefer flying on snazzy new planes such as the Dreamliner or A380, which have up-to-date entertainment systems, quieter cabins, electric outlets and Wi-Fi, and they're willing to pay more for a better experience.
If you're a self-contained traveler who can entertain himself and has battery backup, a lesser plane may offer savings.
The lowest fares are often on airlines whose reputations for customer service aren't always stellar. There's a reason it costs less to fly to Zurich on Aeroflot or Ryanair than on Swiss.
If you wait for the lowest fare, the only seats available may be middle seats near the lavatory. Buying a fare earlier before departure often gives you a better selection of aisle and window seats, but be aware that you sometimes must pay for those better spots.
Delta sells some fares that cannot be changed or refunded under any circumstances. These fares might be $40 or $50 less than fares that can be changed. American and United are following suit. Although it costs to change a ticket, at least you might get something back if you need to cancel. These fares often require a fee to select a seat.
Southwest Airlines might have a slightly higher fare, but there are no fees for checking bags, and if you cancel or change you get to use the value of the ticket on another trip without paying a penalty or fee.
Spirit lets you carry on a purse or a small backpack. But a sample booking for an April 7 flight to Cancún, Mexico, shows that its standard carry-on bag fee, paid at the time of booking, is $35. Before online check-in, that climbs to $40. During online check-in, it goes to $45. At the airport it's $55. At the gate it's $100. Checked bags follow a similar (and, in some cases, slightly less expensive) schedule.
Go to your carrier's website to read about its fees for bags, changes, food and more.