Frequent flyer programs typically have their own currency – Miles. To calculate those miles, airlines use the shortest distance between two airports. Since its standard in aviation to apply miles as a measurement for length, they soon had been implemented as an operand for the airline’s loyalty programs.
Most carriers adopt the distance only as a base for their calculation. Depending on the booking class, there might be a multiplicator that influences how many miles a traveler is credited with. Expensive flights in First Class will get you more miles than discounted Economy Class tickets. So far, so obvious.
If you want to have a closer look at how to calculate your miles, check out this article:
Once you get familiar with the topic of frequent flyer miles, you’ll realize that there are two types of miles out there: award and tier miles.
Tier miles
Tier miles are the kind of miles you will need to obtain elite status. In contrast to award miles, they can typically only be earned by flying.
Expiration of tier miles
Your account for tier miles will be reset once a year, on December 31st. Or every 12 months, starting on the day you signed up for a membership. So you have to start earning over and over again — year after year.
Some programs have a so-called lifetime account. To reach a grand goal of a million miles or so, all your tier miles will be saved, and if you manage to earn such a large sum, you might be granted some kind of permanent elite status.
Award miles
You can use award miles to get free flights or nights at hotels, sometimes shops online or redeem them for rental cars. The possibilities depend on the frequent flyer program.
Award miles can often be earned by using a particular credit card, staying at cooperating hotels or merely flying. In some cases, you can also buy award miles.
Expiration of award miles
There’s no general rule as to when award mile expire. Some programs guarantee that they will stay valid forever. Sometimes the use of a carrier branded credit card will save them from expiring.
The most common way of handling this topic is the requirement to keep your account active. So you need to earn or spend one mile a year, and the rest will stay where they are.