The deal to create a £100bn AUM wealth manager giant was first announced in April.

The merger between Rathbones and Investec’s Wealth & Investment UK division has valued the combined businesses at £839m, according to the firms.

The merged business - designed to "create the UK's leading discretionary wealth manager" - will operate under the Rathbones name.

The enlarged Rathbones Group will remain an independent, listed company operating under the Rathbones brand with Investec Group as a long-term, strategic shareholder.

The deal received FCA approval in June. 

Expanding its Financial Planning presence will be one of the key aims for the merged business, it said.

The merged company says the deal will also, “enhance the client proposition across banking and wealth management services for both groups.”

Rathbones has been steadily expanding its Financial Planning arm and in 2021 bought Financial Planner Saunderson House for £150m.

At the time Saunderson House had £4.7bn in Funds Under Management or advice, 2,200 clients and 55 financial advisers. Clients' average portfolio size was £2.2m. The acquisition of Saunderson House increased the number of in-house Financial Planners at Rathbones from 25 to 80.

Investec Wealth has also been increasing its Financial Planning exposure and in July last year acquired Edinburgh wealth manager and Financial Planner Murray Asset Management for an undisclosed sum. Murray Asset Management’s 20 staff transferred to Investec Wealth & Investment.

Under the terms of the deal Rathbones has issued 27,056,463 ordinary voting shares representing 29.9% of the Rathbones enlarged ordinary voting share capital, and 17,481,868 convertible non-voting ordinary shares, giving Investec a 41.25% share in Rathbones.

Investec has also appointed two non-executive directors to the Rathbones board. Investec Group has nominated Ruth Leas, CEO of Investec Bank, and Henrietta Baldock a non-executive director of the Investec Group, as its two non-executive directors. The appointments are subject to regulatory approval.

Ciaran Whelan of Investec Group will also continue to play a role in the integration process.

Rathbones and Investec say the key aims of the deal include:

• enhancing the client proposition in investment management, Financial Planning, fund management and banking services
• creating a multi-channel distribution capability across private clients, intermediaries and charities, through an expanded network of 23 locations in the UK and Channel Islands
• leveraging Rathbones' investment in technology and operating model to deliver an optimal client experience while improving operating efficiency across the larger combined business
• delivering significant value creation through “target annual run-rate cash synergies” of at least £60 million, driven primarily by cost savings as well as higher net interest income
• establishing a long-term, strategic partnership between the enlarged Rathbones Group and Investec Group to leverage attractive collaboration opportunities.