He has been appointed by 3's joint chief executive Bob Fuller and replaces Lisa Gernon, 3's strategy and marketing director, who moves into an advisory capacity from June 1.
Bob Fuller, Co-CEO 3 UK said: "When I joined 3 UK I initiated an operational review that is now underway. As part of that process and in order to ensure the review is rapid and thorough I have appointed Gareth Jones as chief operating officer.
He added: "The role reflects the company’s shift from a development phase to being operational and will have a specific customer focused remit. I worked with Gareth for ten years at Orange and his skills are an excellent fit for the new role and the challenges of offering customers a new technology."
Jones arrives at the mobile phone company after a multimillion-pound advertising campaign, created by TBWA/London, to support the March launch of the first of the UK's third-generation mobile phones, which have failed to capture the public's imagination.
To date, it is estimated that only 20,000 people has so far signed up for the 3 service. Handsets alone for 3 cost around £200 with £59.99 or £99.99 monthly charges for services.
The advertising has focused heavily on content that the 3 service offers, including Premier League goal clips, which coincidentally cost 3 £30m.
Jones was previously sales director at Orange, where he also worked with Fuller for 10 years.
According to Jones: "My job is to address all operational issues and to ensure customers receive the best possible service from 3. I believe that my experience at Orange, where I worked closely with Bob Fuller and other Hutchison colleagues, has put me in an ideal position to take on this challenging role."
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