The pitch against incumbent TBWA\London was overseen by Air Miles managing director Drew Thomson, who invited Grey to pitch and incumbent TBWA to defend it.
The loyalty card scheme has been using Grey for a promotional roadshow around 18 cities in the UK to drive awareness of its recently relaunched website, which pits it against online travel agents such as Lastminute.com and Travelocity.
Grey's win follows the move of Garry Lace, who used to look after the Air Miles account at TBWA before he took up the UK chief executive's role at Grey at the end of last year.
As much as 50% of the account is expected to be spent below the line as Air Miles steps up its battle against Nectar, the loyalty scheme run by Loyalty Management UK with partners including Sainsbury's, Debenhams, Vodafone, Ford and BP. The rest of the spend is expected go on regional advertising.
Air Miles reacted to the launch of Nectar earlier this year with the 'great Air Miles giveaway' campaign, which aimed to fill an extra 500,000 seats on BA flights.
It was backed by a major advertising campaign through TBWA and Air Miles' biggest ever direct-mail campaign.
Air Miles has added House of Fraser and BT to its list of partners, which already includes Tesco, Shell, Hilton and NatWest.
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