For example, Fiji Airways has an $899 round-trip special between the island nation and Los Angeles for early 2015 travel. "That's about $250 less, maybe even $300, than normal," he said. For domestic fares, Southwest, Virgin America and JetBlue all have sales this week for travel this month into next spring.
Even if you're not ready to book now, shoppers can take advantage of airlines' online shopping malls, which often offer bonus deals this time of year, said Kelly. For example, Macy's, Blue Nile and Kmart are all doubling promotions to 4 miles per dollar spent through United's Mileage Plus Shopping. At Delta's SkyMiles Shopping, Famous Footwear has doubled its rate to 8 miles per dollar.
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Although sale fares tend to sell out fast, take the time to compare offers and scrutinize terms before you book. "Probably the biggest hiccup are the blackout dates," said Gabe Saglie, senior editor for deal site Travelzoo. Holiday travelers may need to book creatively to make the sale dates work. Other deals, particularly packages, can have tough policies for cancellations and changes—worth weighing in the face of winter storms.
Airlines typically waive change fees when bad weather hits, but that could still leave travelers out money from their hotel, cruise or tour. Maybe even without a vacation. "The reality is, if we have a limited window of opportunity to travel to a destination, the fact that they're waiving fees may not help," Saglie said.
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If cancellation policies are unforgiving and the trip is expensive, it can help to consider travel insurance. Some credit cards, including a few from Chase and Citibank, even offer to reimburse cardholders for nonrefundable portions of their trip stemming from a delayed or canceled flight, said Hobica.
To limit the chance of problems, aim for flights leaving early in the morning, which are less likely to be delayed or canceled. Nonstop is best, but if you must book connecting flights, look for stopovers in warm-weather cities, said Hobica. "Connect through Phoenix or Dallas rather than Chicago in winter," he said. "You're less likely to have a misconnect due to weather."