By Jeremy Simon
Published: May 11, 2007

With some airlines now setting earlier expiration dates on frequent flier miles, airline credit card holders who do not take to the skies on a regular basis are in danger of losing their hard-earned miles. However, there are some relatively easy methods that cardholders can use to prevent their airline miles from simply disappearing.

Airlines have decided to make their miles expire sooner since unused airline miles appear on the carriers’ financial statements. By reducing the number of miles to be redeemed, airlines can bolster their financial results.

Among the airlines that have announced changes to their frequent flier programs, United Airlines said beginning at the end of 2007, miles that remain in accounts without additional earnings or redemptions for 18 months in a row will expire, down from 36 months previously. On January 3, 2007, US Airways introduced a similar rule. Meanwhile, Delta Air Lines cut the amount of time its mileage accounts can remain inactive to 24 months from 36 months.

But airline credit card users looking to save their miles don’t need to do much. One of the first things to do is to figure out how many miles they have on various airlines. By visiting the airlines’ websites, travelers can see their mileage balances and expiration dates. Alternately, they can pay a service like mileagemanager.com to consolidate various airline totals into a single statement and provide email alerts about expiring miles.

Each year, credit card holders can take a look at mileage expirations, focusing on those airlines whose miles will expire before then next checkup. Generally, those will be miles for airlines that have not been flown lately or whose credit card has not seen recent use.

By booking a flight on most major airlines, credit card users can earn miles that will reset the mileage expiration countdown. Also, travelers in need of account activity can often gain miles when paying for rental cars and rooms at hotel chains, which may let the cardholder select the airline to credit for the transaction.

Separately, eating at restaurants can help keep airline miles from vanishing. American Airlines, Continental, Delta, Northwest, United, and US Airways allow consumers to register credit cards or debit cards, which can then be used to earn miles when dining at a network of restaurants.

Restaurants are listed by Rewards Network Inc., and at least one of its over 8,000 North American eateries is likely near to, or already visited by, the cardholder. A credit card or debit card can earn points in just one loyalty program at a time, including non-airline programs, such as Upromise, which Rewards Network also has as partners.

New account activity from paying for a meal or a rental car with an airline credit card can provide the cardholder with enough miles to redeem for a free ticket before the miles get taken back by the carrier, or can at least delay expiration. Miles can be earned through car rentals or eating at a restaurant in a network that awards miles with credit cards that include the Alaska Airlines Visa Signature, the United Airlines Mileage Plus Signature Visa Card, and more from the likes of American, Continental, Delta, Northwest, and US Airways.

Also, a large number of airlines let the consumer earn miles by shopping online using portals liked to the airline’s website. A low-cost way to save miles is through a purchase at drugstore.com or iTunes, as well as by buying a small gift card from the website of a store you often visit in person.

Since mileage redemptions also provide instantaneous reactivation for many airlines, magazines that cost fewer than 1,000 miles or the donation of miles to charity can count as account activity.

With some easy ways to save airline miles for most carriers, it is worth a little effort to keep from losing miles that could be worth a penny or more when redeemed for a free flight.