The agency won the centralised business after a pitch against the incumbents, AMS and Tri-Direct. Walker Media and Zenith Media also pitched for the business.
The majority of A&L's spend is expected to be below the line. Last year it parted company with its creative agency, D'Arcy, when the agency resigned the account after picking up the Capital One business.
Before the review, Manning Gottlieb OMD handled media planning for A&L but the agency's role was scaled down after A&L decided to pull much of its above-the-line spend. The agency no longer works for A&L.
MediaVest Manchester's main role is to focus on direct-response buying for A&L. Its direct marketing agency is Proximity London, which has created a series of press campaigns featuring Snoopy from the Peanuts cartoon series.
A&L has not run a major advertising campaign since last year, when D'Arcy launched its "making questions count" campaign featuring a credulous eskimo.
However, A&L is expected to reinvest in brand advertising next year as it relaunches its brand.
The review, which kicked off in July, was held as part of a process to increase accountability and efficiency. Stephen Leonard, the A&L director of marketing services, oversaw the review. Leonard is part of a new marketing team at A&L after the departure of Tim Pile and Nick Smith, who were both senior marketers, earlier this year.