Sky is 'at a stage in its life-cycle where it needs to behave like an entertainment superbrand rather than a utility company', said director of publicity Adrian Lee, who is likely to shortlist six PR agencies to pitch.
The review spells the end of Cohn & Wolfe's three-year hold on the account - the agency has declined to repitch.
Sky wants to hire an agency with experience in 'brand-building for mass-market products'. Lee said: "We have a strategy to fundamentally shift perceptions of the Sky brand."
The brief excludes Sky channels, which continue to be promoted by various PR agencies and Sky's own publicists. The contract up for grabs is understood to have a budget of around £200,000.
Lee added: "We need to ensure we have the best consumer PR support - we wanted to throw [the account] open."
Sky has 7.4 million subscribers and is seeking to gain 600,000 more by
December next year. The broadcaster wants ten million signed up by 2010.
The final pitch process will be held at the end of November, with a decision likely in mid-December.
Lee is overseeing the pitch, along with director of comms Julian Eccles and consumer PR head Gabby Bennett.
C&W's Sky account was also put up for pitch last year but the agency beat five others to renew its contract.
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