VCCP won the account, which is understood to be worth about £30 million annually, after beating Mother in the final stages of a competitive pitch overseen by ISBA.
18 Feet & Rising, the incumbent, has worked with the building society since 2011, when it won a pitch against Saatchi & Saatchi.
The appointment follows Nationwide’s attempts to broaden its marketing platforms and create a roster of agencies to work with on projects spanning traditional advertising, digital and CRM activity.
At the time of the review, a spokesman for the building society said it was looking at its "creative and brand agency model to reflect a modern, integrated brand and digital communications landscape".
Nationwide wants to position itself as the "true alternative" to high-street banks.