Thompson, who has been at the world's largest mobile operator since 2004, will step down from her role as corporate comms director at the end of August to 'explore new challenges'.
She will be replaced by Christian Cull, who was most recently comms director of Thomson Holidays owner TUI UK & Ireland. He will join Vodafone's UK business at the end of July, having left TUI in November 2011.
Thompson was formerly director of consumer, enterprise and brand for the wider Vodafone Group, before moving to Vodafone UK to lead corporate comms in 2009.
She has also served as director of European corporate comms at Kellogg's and spent a decade at Burson-Marsteller, where she became managing director.
Cull will work alongside Vodafone UK's head of external comms Richard Wray, head of internal comms Catherine Inwood and head of corporate responsibility and reputation Libby Pritchard.
Cull has also held senior comms roles at BSkyB and Waitrose.
The move follows a year of significant changes to Vodafone's global comms operation.
Matt Peacock joined the telecoms giant as group comms director from BG Group last summer and has overseen a significant overhaul of its comms function.
In March this year the firm ended its seven year relationship with RLM Finsbury, moving to City rival Maitland, and made a raft of senior hires to its external and internal comms teams.
Vodafone Group is also seeking a new global b2b agency to help it promote itself to the global enterprise market, a process led by Peacock and head of enterprise and industry analyst comms Nicola Rossi.