When completed, the merger will create a combined firm of nearly 800 staff with a turnover of approximately £85m.
In Exeter, the combined firm will be known as 'Trowers & Hamlins incorporating Stones Solicitors', for two years post completion, before becoming Trowers & Hamlins.
Jennie Gubbins, Trowers & Hamlins' senior partner, said: "This merger will allow us to build on the successes of our existing Exeter offering. It positions us to grow our regional presence and reputation in the South West region and to build on our existing real estate offering there, in particular helping us to broaden out from our social housing and public sector heritage.
"In addition, for the first time, we will be able to offer corporate and private wealth expertise from a regional base, giving us the opportunity to expand our regional non-public sector practice and better service our clients."
Trowers & Hamlins employs 124 partners and over 700 staff with offices in London, Manchester, Exeter and Birmingham as well as four in the Middle East.
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