Ian Peacock, head of UK and Ireland at the FTSE 250 firm, will join the advisory board of CoInvestor, an alternative investment platform which lets investors put their cash into assets usually reserved for institutional investors.
The six month-old platform has also landed a new round of seed stage funding worth £1.1m.
The startup, which allows private investors to put money into the same investment deals alongside fund managers, will seek to grow further, adding new products and investments. CoInvestor initially launched with an Enterprise Investment Scheme (EIS) product with Oxford Capital and MMC Ventures.
Peacock's appointment is just the latest example of a top Square Mile executive joining a new fintech company.
City heavyweight Lady Barbara Judge joined startup Hibob as chairman over the summer, while Blockchain startup Setl boasts former Barclays chair Sir David Walker, former Bank of England deputy governor Rachel Lomax and ex-Ofcom boss Ed Richards among its executive team.
Rich Ricci, another top ex-banking executive at Barclays, joined fintech startup FreemarketFX as chairman earlier this year while Lord Adair Turner, the former chief of the finance regulator, joined the board of challenger bank OakNorth last year.
Peacock said adding his expertise to the company was just another step in his finance career which has also "very much been in the technology world too" he told City A.M..
Getting the right mix of skills and expertise at a startup, including those from traditional business is, "crucial", he said. However, he added that it was also crucial for executives in traditional businesses to be plugged into the developing world of fintech.
"The world is changing and people who work in big corporate jobs... why wouldn't they want to be involved?" he told City A.M..
"People also want to do more. Their motives change as you get older and more experienced. And doing things like this is pretty inspirational, helping to grow something from the beginning. As an executive it keeps you relevant and informed.
"If you’re in finance and not curious [about fintech], then your’re probably not going to stay relevant for long. And fintech and disruption is clearly not going away. To not have an interest in it would be almost negligent," he said.