By Rachel Reeves,Samuel Norman

Copyright cityam

Nine years ago entrepreneur Matt Clifford took a data scientist to a “terrible pub” to convince him to drop his PhD and create his own start-up.

“You may as well just take the risk, the biggest risk is not taking the risk,” Clifford told a young Barney Hussey-Yeo.

Almost a decade later in 2025, Hussey-Yeo owes a lot to the advice that helped him create a firm that just this year sealed unicorn status with a valuation north of $1bn.

Cleo notched over £100m in revenue last year – an annual rise of 106 per cent.

The fintech uses Hussey-Yeo’s background in tech to leverage AI through a financial assistant that targets young people aiming to solve personal finance queries.

He describes the quick switch as “wild” but not a move he ever takes a moment to regret.

“In that five-year period, I’d have been earning £30k a year, working part-time, doing the PhD…[Cleo] became worth half a billion and was meaningfully liquid.”

Now, as his company gears up for a UK comeback, the straight-talking fintech founder has turned his attention to London’s capital markets following a meeting with an investment banker where he claimed Wall Street “mocks” the City of London.

Betting on AI

Hussey-Yeo credits his background as a data scientist for making him “obsessed with problem solving” and adds he used that skill to make major moves on modern tech way ahead of the boom in recent years.

“I bet on AI agents very quickly and very early. This was nine years ago, they were called chat bots back then. It was called machine learning – not AI.”

Though he got in early, he speaks of challenges when fundraising with investors viewing it as a “dumb idea”.

“It was almost a little bit too early. You didn’t have the transformers.”

However, he sees a stark difference between the public perception now.

“All these venture capitals now who are like AI, AI, AI, thinking they invented it – I can literally name all of these people who were completely sceptics and thought it was not going to work who are now like AI native VCs.”

Cleo’s UK comeback

Hussey-Yeo speaks to City AM as Cleo lays out its plan to return to the UK market after its exit in early 2022 in a bid to target American users, where 99 per cent of its customers were based at the time.

“Regulation was one of the major reasons that I left the UK and made the US the dominant market,” he says.

“We’re supposed to be coming back later this year but when you look at the regulatory environment and when you look at how things are in the UK – it is risky to be in the UK.”

Even Rachel Reeves’ crackdown on the UK’s watchdogs can’t entice the fintech boss.

The Chancellor declared earlier this year regulation was a “boot on the neck of businesses” and watchdogs to “take up the call” of regulating for growth.

The package was also touted as part of Rachel Reeves’ push to encourage firms to stay in the UK for a listing.

Hussey-Yeo says Reeves was right to be “pushing hard” on the matter,but called for a wider conversation on risk appetite.

“When you talk to the regulators they hear the message from Reeves but want to have a conversation about what is actually the government’s risk tolerance.

“If you are going to deregulate and push faster, these conversations need to have a conversation with the Treasury.”

He admits the regulators are “stuck between a rock and a hard place” due to being “pushed very hard by Rachel Reeves in one direction but they’ve not hard that conversation on what is the real risk tolerance – I think that needs to be had.”

A call for action

Whilst hesitant on a UK return, the Sheffield-born fintech founder is eyeing more fundraising for Cleo in the near-term.

“We’ll do another round in January,” he tells City AM – a move that would mark Series D funding for Cleo.

The firm’s valuation has ballooned over recent years and this year finally notched its unicorn status.

“It just got easier and easier for us along the way,” he says. “Acquisition is easier because people are used to talking to our agents.

“The intelligence has got so much better so the products have got better.”

The booming valuation and stellar growth would provide a much-needed boost to the City market, though officials shouldn’t get their hopes up anytime soon.

“You would need some really fundamental reforms to get people to list here,” Hussey-Yeo says.

“It’s doable – but there are a lot of things to do” the self-proclaimed obsessive problem solver says, as he lays bare the issues plaguing the City market.

The fintech boss may argue it’s “doable” but in his mind this won’t be achieved without some major swings.

Radical stock exchange reform

One radical change he proposed was a merger between the London Stock Exchange and one of the US’s major indexes, building on the recent taskforce announced between the two nations.

“Trusted nations trust each other and want to be partners so then the regulators should trust each other as well – and that would be so much easier for firms operating across jurisdictions.

“The UK is only ever going to have finite capital, it’s the sixth biggest economy in the world, but it’s finite”.

He argues the country has become too risk averse to the point it was becoming an “incubator economy” generating start ups that were set to exit to the US.

He described the move of Wise – which transferred its primary listing to the US earlier this year – as a “natural” pathway.

“We’ve missed out on this technology revolution over the last 20 to 30 years.”

Whilst it doesn’t take a data scientist to realise the London Stock Exchange is stuck in a rut, it may take an AI algorithm to outline all Hussey-Yeo’s reasons for avoiding a City listing.