American and Southwest try to block websites tracking frequent-flyer miles

In the past year, American and Southwest have sent cease and desist letters to websites that offer a tracking service for frequent-flyer loyalty programs. American doesn't want third-party sites taking data off its website, and Southwest contends that the independent aggregators threaten security of passenger information, according to the Wall Street Journal.

Websites that track loyalty program miles, hotel and rental car points in one place include sites such as AwardWallet, MileWise and GoMiles, none of which track Southwest flights. Mileage-managing site Usingmiles.com recently deleted American flights from its site, while other sites are negotiating with the airline in order to access data from its loyalty program.

Through such mileage managing sites, travelers can view and keep track of pertinent information, such as when miles are about to expire, or which program is close to an award or elite-status level. Some sites will show the dollar amount for a ticket as well as its cost in miles, a comparison that can require multiple searches on an airline's website, according to the Wall Street Journal.

At issue, is that many airlines regard miles earned, as well as account passwords, as property of the airline. "Terms and conditions of many airline programs prohibit travelers from their sharing account numbers and passwords," the Wall Street Journal reports. However, most airlines have thus far allowed mileage-manager websites to access data from their loyalty programs.

You can do some calculations before you use your miles for anything other than travel. Check out Best ways to spend airline miles.

Two Airlines Battle Mileage-Tracking Websites [WSJ]

—Maggie Shader