Oliver Kent-Braham spent about six months as a banker at Investec, then left to start a company with his twin brother Alexander and engineer David Goate. The company was incorporated in 2016 as Twin Thinking and renamed Marshmallow in 2017.
The idea came from a Canadian friend who had just moved to the UK and kept getting very expensive car-insurance quotes. The twins saw that deeper data could let them insure drivers with thin UK histories and low credit scores.
For their first 10 months they worked from the lobby of a Virgin Active gym on a £80 membership. They chose the name Marshmallow partly because insurers' names tended to start with A. In 2018 they raised a $1.2 million seed from Investec and Passion Capital, and won a naming dispute with Marsh McLennan.
A $85 million Series B in 2021 made Marshmallow a unicorn at $1.25bn. The Financial Times ranked it the second fastest-growing company in Europe in 2023, at 660% compound annual growth. A raise of about $90 million in 2025 valued it at about $2bn.