Maxus Hong Kong has started working on the account already.
The Swatch Group has a wide portfolio of premium watch brands, including the popular Omega, Longines and teenager's collectable Swatch plastic watches.
Reported on 22 October, Mediacom outgunned three agencies to scoop the Swatch Group's China media account following a four-way pitch.
The aim of the pitch, which took place in September, is to consolidate media duties for all brands under the group into a central buying team driven out of the company's Swiss headquarters.