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Delta SkyMiles (Edit)

The "big three" U.S. airlines -- American, United and Delta -- have very similar frequent flyer programs. While Delta's SkyMiles program is not significantly different from the others with regard to earning miles, redeeming miles, partnerships or promotions, noteworthy differences do exist -- both with regard to the frequent flyer programs and the air-travel products offered. In general, Delta treats its highest-level frequent flyers better than the other airlines treat theirs, but it treats its lower-level frequent flyers slightly worse. Leisure travelers seeking the very cheapest tickets may want to choose another program, as upgrade opportunities will be severely limited on Delta. On the other hand, Delta flies only two-class aircraft, rather than a three-class aircraft like American and United fly on many routes, so an upgrade on Delta is always to a top-of-the-line seat, making it more valuable. Delta, like most airlines, has an affiliated credit card; Delta's is issued by American Express.

Features

Flights on all SkyTeam airlines (including Delta) earn "base" mileage, which counts toward elite status on Delta. The top two elite levels, Platinum and Gold (requiring 75,000 and 50,000 annual base miles, respectively) earn 100% bonus mileage; the lowest elite level (requiring 25,000 annual base miles) earns 25% bonus mileage. Members who achieve the top elite level receive six systemwide upgrades. The lowest elite level (Silver) can request upgrades on most fares one calendar day before scheduled departure; the middle level (Gold) can request these upgrades three calendar days in advance; and the top level (Platinum) can request upgrades five calendar days in advance.

Pros

SkyMiles is a solid program with numerous earning opportunities. The co-branded American Express card that offers double miles for many purchases is a benefit that other programs once had but discontinued, so that's a real plus for Delta. Being able to mix and match award travel makes it easier for members to get award seats -- even though sometimes it's at a higher cost -- at least you've got a seat.

Cons

Many flyers complain that Delta does not provide an adequate inventory of seats for award travel, particularly on desirable routes. Of course, Delta would prefer to sell those seats, if possible, but frequent flyers need to be able to use their miles, too! Delta is famous for holding back upgrades until the last minute. Delta personnel can be extremely rigid at times, much more than at American or United. In keeping with Delta's "Simply Good Business" philosophy, front-line employees are not empowered to bend the rules, even when it would make sense to do so. Changes such as taking away the complimentary lounge membership for Platinum members has tarnished the Delta metal for the most frequent flyers.