Airline frequent flyer miles can be used for future free travel. These programs are easy to join and make it simple to keep track of your total miles.
Most airlines offer a frequent flyer program that allows travelers to accumulate air miles in a frequent flyer account. Miles can be earned both by flying and by participating in various other spending opportunities, such as renting a car or using a mileage credit card. The miles can be used to book travel or upgrade a seat on future flights. Airline miles are like a type of currency, although there's technically no monetary value to them. Many travelers pick a favorite airline and prefer to keep all their miles in one place to help earn airline status and get free flights.
If you are already a member of a frequent flyer program, like American Airlines' AAdvantage or United Airlines' MileagePlus, and you have been including your frequent flyer number on your travel reservation, log in to your account to see your total number of miles, available online or in the airline's app. When you visit an airline's website, look for the login tab or box to access your account. For example on the United website, click on the MileagePlus tab. Most apps keep you logged in, so your total miles should immediately appear on the initial page. You should see both your total miles and the number of miles you've logged this year, as well as your airline status (if any).
Call the airline if you don't know your login for the website or app. Customer service will also be able to provide your mileage total.
If you haven't joined a frequent flyer program but do fly a lot, it's still possible to claim some miles. Fill out the enrollment form online for a specific airline (or for several if you have potential miles on various airlines) and keep track of your new membership number. Travelers must be 18 years old to join most frequent flyer programs. It's possible to request credit for recent flights as a new member, although some restrictions will likely apply. For example, United's MileagePlus program allows new members to request credit for qualifying flights that took place up to 30 days prior to the enrollment date. For a fee of $50, new members can ask for credit for flights up to six months prior. Check with your chosen airline for its policy on retroactive credit.
Once you have enough miles, you can book a free flight or use the miles to upgrade an existing reservation to business or first class. Each airline's website has a booking page for rewards bookings to check for possible flights. Be sure to log in to your mileage plus account before booking. Some airlines offer various types of rewards fares so it's always best to do some research and look into what option is the best use of your miles vs. your money. There are many dozens of websites that can help navigate using airline mileage programs, including The Points Guy and A View From The Wing.
Zemler, Emily. "How to Find Out How Many Air Miles Points You Have." Travel Tips - USA Today, https://traveltips.usatoday.com/out-many-air-miles-points-61414.html. 28 October 2017.