UPC's services including broadband internet, telephone and television, and W&K is charged with redefining the brand in the digital age.
It won the business after a pitch that was run by Michaela Adami-Schrott, vice-president of marketing communications UPC Broadband.
Tim O'Kennedy, managing director of W&K Amsterdam, said: "With UPC, we'll be working centrally in a fast-developing digital territory, on branding and communicating a digital offering that affects the way we all live."
A second brief managed by Aad Boon, director of marketing and communication for UPC Netherlands, to support the launch of UPC Digital TV in the Netherlands, is also up for grabs.
UPC offers services in 13 countries in Europe including France, Belgium and the Czech Republic, reaching 14m homes and 10m customers.
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