The agency, which specialises in promotional and direct marketing, would not reveal the exact spend of the campaign nor the other agencies that took part in the pitch for the account.
The campaign is due to launch during the summer across all supermarkets to reinforce Kingsmill as a leading player in the branded rolls sector.
Kingsmill brands include its Soft White Rolls, which claim to be the best-selling six pack on the market, Wholegrain, White and Tasty Wholemeal, which will permanently move from a six pack to a four pack at the time of the promotion.
The pack size alignment and on-pack activity has been designed to encourage loyalty, increase frequency of purchase and stimulate further growth in the non-white sectors.
Dynamo's clients include Cereal Partners, Danone, Dairy Crest, Sainsbury's, Unilever and United Biscuits.
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