The acquisition forms part of an expansion drive and follows Remarkable’s recent office openings in Manchester, Bristol and Cardiff.
Remarkable Group was founded in 2004 in Southampton and is a fully integrated agency with clients including Aldi, Cash Converters and Taylor Wimpey.
It was ranked as the UK's 69th biggest agency with fee income of £2.8m in 2013 in PRWeek's latest Top 150 Consultancies report, having climbed six places.
Manchester-based Pendragon was founded in 1989 by managing director Alex Doyle and specialises in managing stakeholder communications during the planning process for large-scale infrastructure and energy projects. It did not feature in the Top 150.
Remarkable Group chief executive Stephen Pomeroy said: "Remarkable Pendragon is a first for the UK stakeholder consultation market: an agency dedicated to helping companies achieve positive planning outcomes and wider stakeholder and government relations for infrastructure and energy projects. I have admired the work of Alex and his team for many years and I’m delighted to be able to welcome them into the Remarkable Group.
"The expertise of Remarkable Pendragon, its national reach, and innovation in digital and creative consultation solutions will provide clients with an unrivalled offering that brings measurable business results. We will focus on supporting infrastructure and energy clients through planning permission, construction and into operation, with communication strategies designed to build strong community, political and stakeholder relationships."
The acquisition brings Remarkable closer to the size of PPS, regarded as one of the leading stakeholder consultation specialists, which reported fee income of £4.5m, placing it 49th in the Top 150.
Doyle added: "We are delighted to become part of the Remarkable growth story, and look forward to working with our new colleagues to offer infrastructure and energy clients an exceptional service. We are shaking up the way stakeholder consultation is delivered in the UK."