Media Palette takes charge of the account on 1 April and will handle it through the end of the year.
The company's senior planner, Amanda Chien, who oversaw the pitch, said the Chunghwa Post win is a "milestone" in that it is the first time the postal service has bundled its promotional budget into a single account.
"Branding is what Chunghwa Post needs now," said Chien. "The postal service changed its name several times in the past few years. During the previous DPP administration, the name was changed to Taiwan Post. Now under the KMT it has switched back to Chunghwa Post. People don't know what to call it."
In the past, each of the postal service's many divisions had individual promotional accounts.
Last year, there were nearly a dozen media pitches, with Media Palette, Carat and Mindshare each winning many of these small projects.
Creative was awarded to a handful of small advertising agencies. The budgets for those accounts were small, under US$30,000 for production fees.