Frequent Flyer Miles Secrets Revealed: How to Fly for Free

Most of us fly for work or for fun, but the prices seem to go higher every time we check kayak.com. Want to fly for free next time? Here's how you can turn your daily purchases into that free flight (and many more to come).

First, you have to sign up for the airline's free frequent flyer program. It's a quick online form that tracks your flights and tallies up their miles. You can sign up with your preferred airline or with every airline. Just look for it on the airline's homepage (links below). Once you're signed up, make sure to input your frequent flyer mileage number whenever you book a flight with that airline. All these 'miles' flown will add up eventually to a free flight.

Another way to earn miles is by signing up for an airline credit card, found on their homepage. You'll earn a first-use bonus of around 30,000 miles and the card is free for your first year and around $100 for subsequent years. For every dollar you spend on the card (a $3 coffee a day really adds up), you'll earn 1 mile.

You can also earn miles for hotel stays and car rentals. And, the airline credit card package often includes a free piece of luggage when you fly that airline, priority boarding, access to airport lounges, and much more.

Here's how it works: a roundtrip from New York City to the West Coast is approximately 2,500 miles, while a roundtrip from New York to western Europe is approximately 3500 miles. Your monthly credit card spending is $1,500 (i.e. 1,500 miles). A free national flight 'costs' around 30,000 miles from your mileage bank and an international flight is around 60,000 miles.

So sign up for that frequent flyer program and start earning miles towards your next free flight!

American Airlines
United/Continental Airlines
Delta Airlines
Jet Blue
Virgin America