For a better airfare deal, divide and conquer

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To save on your next vacation, consider dividing your trip.

Travelers often book nonstop, round-trip fares by default, but that's not always the best bargain. It increasingly pays to consider above board alternatives, such as doubling up on one-way fares, and booking open-jaw flights that incorporate different cities.

"There aren't many hard and fast rules anymore except: Check out the alternatives," said Ed Perkins, a contributing editor for SmarterTravel.com. All it takes is a few extra minutes on a favorite fare search site.

"Compared with 10 years ago, a lot more routes, particularly domestically, the one-way ticket price is really half the round trip," said Perkins.

Fare sales can offer breaks, especially on competitive routes and ones where there's a directional difference (meaning flying from point A to B is cheaper than B to A). For example, a Kayak.com search turned up a $594 Delta round-trip flight between Portland, Ore., and Honolulu in February. The cheapest one-way flights were a $288 American flight to Hawaii and a $207 US Airways flight back to the mainland, netting savings of $99.

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Internationally, the deals can be even better, if you're willing to uncouple your trans-Atlantic flights with those throughout Europe.

"It's a whole different ballgame," said Rick Seaney, chief executive of FareCompare.com. "There are lots of low-cost carriers with weird and wonderful pricing." Use a meta-search site such as SkyScanner.com or Momondo.com, which incorporate many inexpensive carriers into their results.

For travel between New York and Cologne, Germany, in February the cheapest option is a $1,058 Air Berlin flight making one stop. But travelers who book a round-trip to London could pay just $785, and another $80 on a round-trip Ryanair fare between London and Cologne. Total saved: $193.

Open those jaws!

Open-jaw routes (think point A to B to C, and back to A) can offer similar savings. "The big mistake that a lot of people make is to not even think about that kind of booking," said Ari Steinberg, chief executive and founder of Vamo.com, a planning engine specializing in multicity trips.

"They book the round trip, and say, 'I'll figure everything else out later.' " That can lead to more time spent on the road for, say, a traveler making the popular trip among Rome, Florence and Venice, to get back to the airport they flew in from. "You're doubling back, spending time out of your vacation, which is kind of a waste," he said.

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Of course, there are some logistical concerns to consider. Having multiple legs each way that aren't linked can mean you have to exit security to claim your bags and then check in again and be rescreened to continue the trip, said Perkins. (Never mind, pay another checked-bag fee.)

Separate reservations can also create a domino effect of problems if, say, your first flight in the chain is delayed. You won't be entitled to any recourse for missing those subsequent flights, said Perkins, who recently scheduled in a daylong stopover in London to ensure no such schedule hiccups hurt his chances of getting home. "I would never book a three- or four-hour connection," he said.

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A different way to divide your trip is by splitting reservations for larger parties on the same flights. Start your search for a single seat, even if you're traveling as a group of two or more, said Seaney. "That's the No. 1 booking trick," he said. A quirk of airline booking systems is that they search for the best fare for the entire party, meaning you could miss out on cheaper seats.

With that trick, a consumer could snag one $383 round-trip US Airways fare from Boston to Houston, instead of paying $440 apiece for two or more adults to make the same trip. Savings: $57. Call the airline after booking to link the reservations, especially if you're traveling with kids, he said. That reduces the chances you'll be accidentally seated separately.