Challenger bank Monzo is moving out of its offices in east London and into Bloomberg’s old headquarters in Finsbury Square, as it prepares for a major expansion.

The bank has quickly outgrown its City Road offices and is now poised to move 230 staff into the new 40,000 sq ft premises on the fringes of London’s finance district.

Monzo intends to fill more than 350 seats at its new headquarters in the next 12 months, renting out the remaining floors. The building, which it is sub-leasing, has capacity for 650 staff.

“We’re incredibly excited to be moving to our new home in August,” Monzo CEO Tom Blomfield told NS Tech. “When we moved into our current offices on City Road, we thought we’d be here for a while — the amazing growth in customers and staff we’ve seen over the last 18 months means we’re moving sooner than we thought.

“I can’t wait for us to embark on the next stage of the company in a space where we have room to grow over the coming years,” Blomfield added. “Plus I get to have my own desk again.”

Monzo is one of the UK’s biggest challenger banks, having signed up more than 400,000 customers last year and with a total customer count now exceeding 750,000. It enjoys a cult-like status among urban millennials.

Blomfield has previously spoken of his aspiration to attract more than a billion customers, which would make Monzo one of the world’s biggest banks. But he doesn’t intend to provide the full complement of products offered by his rivals.

Instead, Blomfield is seeking to position Monzo as a hub for people’s finances, enabling them to manage ISAs or mortgages provided by other companies through its app. He also wants to help customers find new ways to save money, taking a cut of any savings made from its recommendations.

Key to this vision is a new set of European regulations aimed at ushering in an era of open banking. But banks are making slow progress in meeting the new requirements. In January, it emerged that six of the UK’s nine biggest banks had missed the deadline.

Some have speculated that the biggest threat to challengers such as Monzo is not legacy banks, but the US tech giants, which have the resources and technical expertise to disrupt markets at a speed and scale few businesses can match.

Google, Facebook and Apple are all dabbling in fintech and it’s possible that one of these firms may seek to acquire a business such as Monzo, as may one of its established rivals. As NS Tech revealed last year, Monzo turned down two takeover bids in July 2017 alone.

Blomfield has vowed that he won’t sell out. At a meeting with customers and staff last year, he said: “We’re here because we believe we can build something that genuinely improves the lives of millions of people around the world, and ultimately a billion. If we sell out to a big bank we will not achieve that goal.”