In the year to 31 March 2016, the company reported a turnover of £43.3m, up from £23.9m the year before.
Profits increased from £19.4m to £36.6m.
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Robey Warshaw was founded by veteran investment bankers Sir Simon Robey and Simon Warshaw in 2013.
It has around 15 staff, including partners Robey, Warshaw and chief operating officer Philip Apostolides.
Contributing to its latest financial figures were fees from advising energy firm BG Group on its takeover by Shell.
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Robey Warshaw also advised SABMiller, which was taken over by AB InBev in £79bn megabrew deal.
In addition, the bank is advising the London Stock Exchange on its £21bn merger with Deutsche Boerse, which was announced during the period and so would have contributed to the revenue.