Tangerine won the brief following a competitive pitch involving a number of other agencies.
The agency has been appointed to deliver a strategic and creative comms campaign, using both online and offline PR.
BusinessComparison.com is a price comparison website aimed at small to medium businesses to compare costs of different services.
Sam Gregory, Tangerine b2b’s managing director, said: "The service BusinessComparison.com provides will offer access to a whole new world of information for businesses. We will be working with it to make sure that as many businesses as possible are using and benefiting from this platform."