Pinsent Masons saw global turnover reach £382.3m for the 2015/16 financial year, up 5.5% on the previous 12 months.
The firm said profit per equity partner had increased to £550,000.
It also made 18 partner promotions, and appointed its inaugural external Board member, Pauline Egan, and its first COO, Alastair Mitchell.
Pinsents’ Managing Partner, John Cleland, said: "Our vision is to be recognised as an international market leader in the global sectors in which we operate, and this latest set of results demonstrates further progress.
“It is particularly pleasing that we have managed to sustain growth and profitability while making unprecedented levels of investment into our business. Our partners recognise that if we are serious about becoming international market leaders we cannot stop investing.”
Cleland added: “We have a good deal of momentum in the business and our focus now is on supporting clients based in the UK and elsewhere through what is likely to be a volatile and unpredictable trading period. Some time ago we assembled a multidisciplinary Brexit Advisory Team which is already engaged with clients globally to address the challenges and opportunities linked to Brexit.”
Panel wins included being appointed or re-appointed to act for organisations including Capita, Serco, Peel Ports and Galliford Try.