Lexicon Partners was founded in July 2000 as an independent corporate advisory firm focusing on the financial services sector. The founding team had previously worked together for over 10 years at Phoenix Securities Limited and in the Financial Institutions Group at Donaldson, Lufkin & Jenrette International.

In February 2004, Lexicon Partners announced its expansion into the utilities and infrastructure sectors with the arrival of an experienced utilities team, the senior members of which had previously worked together for over 10 years at Schroders and at Citigroup.