The move is expected to save £100,000 in comms costs in its first phase and will see the comms department report to a new joint comms board.
The council's director of policy and communications Tom Stannard said: 'This new service will transform the way health and social care issues are communicated as it brings them all under one roof.
'Councils and NHS trusts are under immense pressure to cut costs given the financial challenges we all face. In Blackburn with Darwen we believe the adoption of a "total place communications" strategy will help communications support our organisations in meeting those pressures.'
Stannard added that he had identified more than £250,000 of savings from marketing activity through a 'robust evaluation process and development of social media solutions'.
NHS Blackburn with Darwen interim executive director of engagement and partnerships Janice Horrocks added: 'Set against the challenges we face in tackling health inequalities, we need to reduce costs. This arrangement will tick both boxes by improving our ability to communicate ... and delivering cashable savings.'