Before we go any further, I want to make sure everyone is aware of the unit that we’re discussing, the frequent flyer mile.
A frequent flyer mile is a simple enough concept. It is simply a unit of “airline currency” that you earn through flying, using credit cards, etc. You generally earn one mile (sometimes referred to as “points”) per mile that you fly or dollar that you spend with an airline affiliated credit card. There are exceptions to this rule but, for right now, we’ll stick to the “1=1” concept. Each airline has its own program and its own rules but, for the most part, the basics are the same. The programs are always free, so you should sign up for one whenever you fly an airline and hold onto your unique number. When you book a flight, the airline will ask you for your number so that it can give you credit.
Example: I fly from Boston to San Francisco with a layover (stop) in Dallas. The flight from Boston to Dallas is 1,562 miles, while the connecting flight from Dallas to San Francisco is 1,464 miles. I would earn a total of 3,026 miles.
A few days after your flight, you would simply log in to your airline account and it will be updated with your new balance. Miles generally don’t expire as long as you have activity in your account every 18-24 months, but check your airline’s particular program for the specific rules.
Here is a list of links to sign up for the most popular airline programs. You don’t have to sign up for every program right now, but you need to do so before your first flight on the airline so you can get credit.