The company, which has 124 outlets across the UK, has drafted in Leatherhead shop Pheonix to handle consumer PR for its three business units.
These are Restaurants; famed for its distinctive 'fish and chips in an upmarket setting' concept; Express, which is positioned as a fast food chain; and Local, a chain of small fish and chip shops.
It is not yet clear which of the three chains Pheonix will work most on, and work is not expected to begin until October. But Pheonix director Claire Methven confirmed the agency had been hired by the chain, an arm of the Compass Group's Roadside division.
She is to lead a three-strong team on the account, which a Pheonix source said marks the first outsourcing of Harry Ramsden's PR work since its formation in the Yorkshire town of Guiseley in 1928.
The agency and the client both declined to elaborate on specific PR plans but said one reason for the expanded PR function was to broaden the restaurant group's audience.
'We don't want to alienate older customers but we do need try to reach a younger audience,' Methven said.
Harry Ramsden marketing manager Julie Barnes, to whom the account reports, declined to comment.