The announcement, made late on Tuesday evening, climaxes one of the most high-profile pitches of recent years, in which WPP saw off challenges from Publicis Groupe, Interpublic and Omnicom.
The switch ends Lowe's five-year tenure on HSBC's above-the-line account and sees a shake-up of media arrangements that will end PHD's association with the £20 million business in the UK. ZenithOptimedia was the main incumbent on the account in the rest of the world.
Under the new arrangement, JWT will share HSBC with its WPP network stablemate Red Cell. Group M will take on media buying and planning, with MindShare assuming lead media agency status.
Direct marketing responsibilities will be shared by rmg: connect and 141 Worldwide, while Landor picks up HSBC's branding and corporate identity assignment.
The entire account will be co-ordinated by Toby Hoare. WPP hired the former Bates Europe chairman earlier this year to play the leading role in winning HSBC.
A major factor in WPP's appointment is thought to be its strength in Asia compared with Omnicom, its principal rival for the account. "It was our Achilles heel," an Omnicom source said.
Peter Stringham, HSBC's general manager for marketing, praised the "world-class resources" shown by all the contenders. But he added: "WPP's ability to co-ordinate the resources across HSBC's footprint and tailor them to our needs proved decisive."
The inclusion of Red Cell on the roster is intended to provide HSBC with extra creative and strategic resource. It also raises speculation that HHCL/Red Cell in London could be the eventual destination of WCRS's £3 million HSBC First Direct account.
WPP claims that its Merrill Lynch client sees no conflict with HSBC.
The two banks' joint venture was abandoned in May 2002. No-one at Merrill Lynch was available for comment.