The agency group has been renamed The Direct Marketing Group and currently comprises Millennium, fundraising specialist DMS, data management bureau PushButton and print shop Coltec Parker.
Millennium founder Martin Smith says three acquisitions in the DM agency and print sectors will be announced soon.
"Having completed our climb through the agency ranks in Yorkshire, we are now setting our sights on achieving similar success on a nationwide scale," said Smith.
Millennium offers products such as deceased suppression file Mortascreen and Halo, for deceased fraud prevention.