Frank PR has secured the account, which spans consumer and trade media relations.
The account is being run by associate director Jane Hill, who joined Frank from Pilot rival New Look, where she was PR manager, this autumn.
Hill said Pilot's clothes appealed to a wide audience - ‘any woman who loves fashion' - and that publications such as Vogue and Heat would be targets.
She said: ‘Pilot should be on everybody's fashion radar, particularly because so many people are mixing designer and high- street pieces at the moment.'
Frank's brief forms part of an integrated marketing campaign and includes product placement and generating business profiles. The agency was appointed without a pitch.
Privately owned Pilot has 72 stores nationwide.