Hannes Snellman has leapfrogged Roschier to become Finland's largest law firm after a massive 39 per cent leap in turnover.
The firm made e45.9m (£32.18m) in gross revenue in its last financial year, compared with Roschier's e45.1m (£31.61m), but the latter remains Finland's most profitable, with an average profit per equity partner in excess of e1m (£700,000).
The 31 partners at Hannes Snellman will be celebrating the news that the firm's profit rocketed by almost 69 per cent to hit e15.7m (£11m) this year.
Rival Finnish firm Castrén & Snellman also reported strong growth this year, boosting revenue by 19 per cent to reach e25m (£17.52m), from e21 (£14.72m) last year.
Hannes Snellman managing partner Johan Aalto said: "In a very strong market situation we've taken part in a great number of transactions and complex dispute resolution assignments and boosted our operations internationally."
Hannes Snellman is one of the few Finnish independent firms with offices in China, and claims to be the biggest Nordic firm in Russia and the Ukraine, boasting a team of 40 lawyers. The firm employs 260 staff across five offices in Helsinki, Moscow, St Petersburg, Kiev and Beijing.
The firm, famous in Finland for providing personal trainers for its lawyers, intends to keep growing by investing in training for its young lawyers. "During the new fiscal year we will continue to increase our investments in our personnel, with a particular focus on well-being, education, motivation and compensation," said Aalto.