The global insurance-based financial services group picked Fishburn after a competitive pitch process that is also believed to have included FD, M: Communications and previous incumbent H&K.
The Fishburn Hedges team, which begins work on the account immediately, is being led by director Jason Nisse.
Mani Pillai, Zurich's head of group media relations, UK, said: 'We look forward to working with Fishburn Hedges to build on Zurich's strong reputation within the insurance media, to reach out to a wider media audience across a variety of platforms.'
The brief does not incorporate analyst or investor relations, though Fishburn Hedges will support Zurich's in-house team in the UK around its financial statements.
Zurich was founded in 1872. Although based in Switzerland, it has more than 60,000 employees serving customers in more than 170 countries.