The agency landed the business after a four-way pitch through the AAR, which also involved the incumbent Cheetham Bell JWT.
Soul will now begin a marketing push for the brand in September, which will involve TV, print and below-the-line work.
Although Harveys has traditionally spent £5m on advertising, it has allocated an increased budget of £12m for the forthcoming 12 months. The decision to bolster the brand's marketing activity follows the recent appointment of David Rich, who joined as the head of marketing from Alders in May.
Rich said: "Soul's approach, which took account of the look of the store as well as below- and above-the-line marketing, was unique. It was this 360-degree vision that proved it was the agency to take Harveys forward."
Soul's creative partner Bruce Crouch added: "Retailing is the sharp end of business and Harveys is a brand with great potential that will allow us to demonstrate fully our capabilities in this area."
Harveys has 180 stores across the UK. It is part of the Homestyle Group, which also owns Rosebys, Knightingales and Fabric Warehouse.
Its new budget brings its adspend closer to its rival Courts, which spends £16m. However, the budgets of both brands are dwarfed by DFS, which spends £60m on advertising every year.
The appointment does not affect Harveys' media planning and buying account, which is held by MediaCom.
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