Publicis said the deal would give it one of the four leading multi-brand CRM platforms in the consumer goods business in France.
Pour Tout Vous Dire was set up in 2001 to add value to 30 Unilever brands spanning beauty, hygiene, food products and other services. It covers more than five million households.
The deal includes a five-year service agreement under which Unilever has undertaken to keep its brands within Pour Tout Vous Dire.
Meanwhile, Publicis has pledged to expand the operation beyond its current scope and build its credentials.