The U.S. Airways Dividend Miles World MasterCard, for example, advertises up to 20, 000 bonus miles.

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You can go for those bonus miles and cash-back cards, but not all at the same time.

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Instead, credit cards that offer bonus miles with purchases have become the most popular way to earn frequent flyer credits.

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The Miles by Discover Card offers the opportunity to earn 12, 000 bonus miles during the first year you own the card.

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Most airline credit cards boldly advertise tens of thousands of bonus miles.

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Then, in order to get your hands on the remaining 10, 000 bonus miles, you have to execute a balance transfer within 30 days of signing up.

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Nevertheless, I read that the airlines are making more money with a variety of add-on charges, including wider rows in coach, paying for itemized food and additional bonus miles.

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But in the long run, choosing a no fee card over one with not so free bonus miles will leave you with cash in the bank you can use to purchase any flight you want.

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Continental Airlines said they would reward donors with bonus airline miles.

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For that, you get 40% more room, plus a separate cabin from coach and perks like early boarding, expedited baggage handling and 25% bonus frequent-flier miles.

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