The contract - understood to carry fees of around £250,000 - was won after a competitive pitch process that kicked off almost four months ago (PRWeek, 4 October).
RED is to handle consumer, trade and issues work for Premier, which has a portfolio including Branston Pickle, Cadburys Drinking Chocolate, Typhoo and HP Beans.
RED will promote the 30-plus core brands and more than 40 sub-brands, such as Cadburys Chocolate Highlights and HP All-Day Breakfast.
RED managing director David Fuller and deputy MD Mike Morgan lead an account team, around eight to ten-strong, reporting to Premier group marketing director Howard Beveridge.
Fuller said the agency would develop a 'brand-by-brand' strategy, adding: 'The challenge is to bring the brands from the back to the front of the cupboard.'