SkyMiles

SkyMiles is the frequent-flyer program of Delta Air Lines that offers points (or "miles") to passengers traveling on most fare types, as well as to consumers who utilize Delta co-branded credit cards, which accumulate towards free awards such as airline tickets, business and first class upgrades, and luxury products. Created in 1981 as the "Delta Air Lines Frequent Flyer Program"; its name was changed to SkyMiles in 1995. Delta claims that it is the only major U.S. airline without mileage expiration, so travelers can redeem awards at their leisure. The airline also has a separate SkyBonus program that provides small to mid-sized business owners with a way to earn points for trips taken by employees, good towards free flights, upgrades, Silver Medallion status and other travel awards.

SkyMiles allows both round-trip and one-way redemption but at full round-trip pricing, with economy awards starting at 15,000 miles.

In addition to its Delta Connection, Delta Shuttle and SkyTeam alliance partnerships, Delta offers frequent flyer partnerships with the following airlines:

Delta offers four tiers of elite status within the SkyMiles program. These are known as Medallion statuses and can be achieved by flying a certain number of Medallion Qualification Miles (MQM) or Medallion Qualification Segments (MQS) between January 1 and December 31 each year. Beginning in 2014, a certain number of Medallion Qualification Dollars (MQD) is required for the US members in addition to either the MQM or the MQS requirement.

Delta Private Jets Card holders receive Diamond Medallion tier status.

Medallion status entitles members to unlimited complimentary upgrades, subject to availability, on most published economy fares on Delta and certain Delta-designated codeshare flights in North America within or between the United States (excluding Hawaii) and Bermuda, Canada, Central and South America, the Caribbean and Mexico. In addition, preferred coach seating such as in the Economy Comfort section is set aside for medallion members for when first and business class upgrades are not available.

When the frequent flyer program was first established in 1981, new members were awarded an enrollment bonus of 10,000 miles.

On May 1, 1995, Delta Air Lines modified its frequent flyer program. In addition to renaming it "SkyMiles", mileage expiration policies were put in place. Miles from the old program would never expire but newly earned miles in the SkyMiles program would if there was no account activity for three years. Beginning January 1, 2007, expiration was triggered by two years of no activity. At the same time, the old Frequent Flyer Program miles were combined into SkyMiles, effectively negating their unlimited shelf-life. Delta's most frequent patrons still refer to "Silver Medallion" status as "FO" short for "Flying Orchid" after an early Delta loyalty acknowledgement program. This is ostensibly to avoid confusion between "Silver Medallion" and "SkyMiles."

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