He left a top banking job to build his own bank | Mark Mullen, Co-founder Atom Bank

Interviews with Leaders in Fintech & Web3

Interviews with Leaders in Fintech & Web3
He left a top banking job to build his own bank | Mark Mullen, Co-founder Atom Bank
Jun 15, 2026 Season 2 Episode 28
Work in Fintech

Today's guest is Mark Mullen, co-founder and CEO of Atom Bank, the UK's first app-based bank and the first digital challenger to win a full UK banking licence. 

Mark is a self-described accidental banker who read history at university, spent 24 years inside HSBC Group, and ran First Direct, one of the most innovative banks of its era. 

Then, in his mid-40s, he walked away from a comfortable seat at the top of the industry to build a bank from scratch in the Northeast of England, not London. 

He has watched telephone banking, internet banking and mobile banking come and go, and now sits inside the AI wave trying to work out what it actually changes and what it does not. 

This conversation goes past the technology and into the things that endure: trust, people, and why the UK banking sector is still far less disrupted than everyone assumes.

In the full episode, we cover:

- Why banking was "made to be digitalised", and who wins because of it
- How Atom uses Gemini, Claude, and other AI tools in their workflow
- Why AI could cut a third of operating costs in three to five years
- Why the same banks still dominate UK mortgages a decade on
- Why Atom runs a four-day week, and why Mark keeps defending it
- The one trait Mark values most when hiring young people
- His advice for anyone starting out in the AI era

A masterclass in building for the long term, from someone who has done it without the hype. Worth your time whether you are in fintech or not.

Connect with Mark Mullen:
https://www.linkedin.com/in/mark-mullen-5330458a 

Matthew Cheung (Host & Founder Work in Fintech):
https://www.linkedin.com/in/matthewcheung50/

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