Europe in Summer

LAST YEAR’S SWEET SPOT: 21 TO 22 WEEKS IN ADVANCE You may already be too late to score a cheap flight to Europe this summer. The booking window for the cheapest tickets has moved further out, from 11 or 12 weeks in advance in 2009 to 21 or 22 weeks in 2011. (Average round-trip fares rose to about $1,500 last year from $1,100 in 2009; this year’s outlook is no better.)

To boost your savings, take the least expensive route to Europe you can find. Then concentrate on getting to your ultimate stop cheaply.

“I look into the cheapest fare into a hub like Berlin,” said George Hobica, founder of Airfarewatchdog.com, which scours the Web for bargains. “Then I figure it out from there.”

He said this may involve taking the train or flying a budget carrier like easyJet or Ryanair to the final destination. Spanish airports like Madrid tend to be cheaper than London or Paris, he said. Dublin and Shannon also tend to be cheaper jumping-off points.

Whatever you do, don’t wait until the last minute. Last year, average fares for tickets purchased less than a week before travel were about $2,600, almost double the price of those bought at least 28 days in advance. And if you’re visiting London during the Olympic Games, July 27 through Aug. 12, expect to pay a premium.

Caribbean in Winter

LAST YEAR’S SWEET SPOT: 11 OR 12 WEEKS In 2009 and 2010, the cheapest airfares went to procrastinators who purchased tickets just two weeks in advance at a saving of about 8 percent. But last year, the pattern took a sudden shift, with the cheapest tickets bought much further ahead.

“Certainly you’ll want to start shopping plenty early to get a gauge on pricing,” said Mr. Seaney of FareCompare, who recommended hunting for airfare as early as three months in advance, especially for hot spots like Costa Rica and out-of-the-way islands, which lack the airline competition that tends to keep prices in check.