The deal, announced on Tuesday, will hand over control of EBS Management to Embark, including Alpha Trustees, EBS Pensioner Trustees and EBS Self-Administered Personal Pension Plan Trustees.
The acquisition takes Embarks AUM to £10.7bn and its number of clients past 100,000.
It has been fully approved by the UK Takeover Panel but remains conditional on final FCA approval.
Kate Ragnauth will continue to lead the EBS team in London as principal and will join the executive team at Embark.
Embark’s latest acquisition follows its takeover of The Adviser Centre in October 2016 and the takeover of DFM DISCUS platform at the end of March as part of its strategy to acquire and hold a range of financial service businesses that add to its retirement offering.
Phil Smith, group chief executive of Embark, said: “The nature of the EBS business fits perfectly with our long-term plans.
“It has excellent people, one of the best-managed books of business in the Sipp industry, and high-quality anchor distribution clients.
“It offers excellent value to us, and with our digital and technical capabilities, EBS will trade profitably going forward.”
Charles Stanley and Embark will continue to work as partners on Sipp and Ssas services to the former’s clients, and EBS will continue to operate Sipp products under the Charles Stanley brand.
Paul Abberley, CEO of Charles Stanley, commented: “We are delighted with this transaction. It is simultaneously right for all stakeholders of the EBS business, present and future, and most importantly the underlying consumers.
“We look forward to a long commercial partnership with the team at Embark.”