The confectioner will move its six-figure brief to Fishburn Hedges in January 2009, following a lengthy pitch process.
The account is understood to be worth close to £500,000 annually and has been held by Weber Shandwick for more than a decade.
It is believed to be one of the agency's biggest public affairs accounts, although Weber Shandwick sources insisted it had a number of other major public affairs clients.
PRWeek revealed the account was under review three months ago (PRWeek, 13 September).
The win is a welcome boost for Fishburn Hedges' public affairs arm. However, insiders suggested the new brief would have a far greater consumer focus.
Nestle head of corporate comms Sam Fulton said: 'Following a change in its agency requirements, Nestle... has decided to appoint Fishburn Hedges to provide support for its UK corporate affairs activity.
'Weber Shandwick, which has provided a highly valued service to the company, will continue to provide public affairs support to Nestle in Brussels.'
Weber Shandwick's corporate and public affairs MD Michael Prescott said: 'Nestle has been a tremendous client and remains a very significant client internationally.'