Disappearing into thin air

With airline-partner programs that let travelers earn miles for everything from dining out to ordering contact lenses, there is no shortage of ways to rack up frequent-flier miles these days. But redeeming them for a free ticket — as many travelers have learned — is not as simple.

Blackout dates, limits on eligible seats, and competition for popular destinations often make it so difficult to trade miles for flights that travelers just give up.

But if you have not touched your frequent-flier accounts in a while, now might be time to do some mileage upkeep. At least two major carriers — Delta and USAirways — are reducing the amount of time a frequent flier can leave an account inactive without forfeiting it.

Starting Jan. 31, USAirways Dividend Miles accounts will be closed, and all miles forfeited, if there has been no activity, either earning or burning miles, within 18 consecutive months. That’s down from the current three-year mileage account expiration date.

Delta is cutting the life span of frequent-flier miles from three years to two years and has instituted a retroactive deadline. On Dec. 31, miles in SkyMiles accounts that haven’t been touched during the last two years will expire. The airline says it is sending letters to frequent fliers whose miles are in jeopardy and will follow up by e-mail. But Delta frequent fliers who have not updated their postal or e-mail addresses — or who regard airline messages as junk mail they don’t need to read carefully — could be caught off-guard.

“What has always kind of given me pause since I’ve been aware of this,” said Tim Winship, publisher of Frequent Flier.com, which tracks loyalty programs, “is the way they are doing it — retroactively. This will catch a lot of their members unaware unless they do a real bang-up job at getting the word out between now and the end of the year.”

The introduction of the shorter life spans, he said, could very well trigger a change in what has been a common rule of major carriers: that miles do not expire as long as there is some account activity every three years. For now, airlines including American, Northwest and United are sticking with the three-year rule.

Some frequent fliers may be confused to hear that they could lose their hard-earned miles. That’s partly due to airline semantics. Northwest and Continental, for example, insist that miles do not expire. But accounts can be canceled. If no activity is posted for a given period (three consecutive years for Northwest, 18 months for Continental), the account is subject to termination, and accrued mileage can be lost.

Some discount carriers, such as Southwest and ATA, known for having among the least consumer-friendly award policies, have loosened their rules. Until August 2005, Southwest Rapid Rewards credits expired after just 12 months. That policy has since been liberalized to allow credits to stay active for 24 months.

ATA announced earlier this month that points earned on qualifying flights and partner transactions on or after Oct. 1, 2006, would be valid for 24 months instead of 12.

JetBlue points still expire 12 months after they are earned. But in August, JetBlue began allowing frequent fliers to extend the longevity of points for a year by using a JetBlue Card from American Express either to buy a JetBlue ticket or to spend $200 on other purchases.