Six months ago, Flex raised $60m and called it a Series B. On Tuesday it said it had raised another $70m, and rather than move down the alphabet, it settled on a Series B1.
The round was led by Halo, the investment firm set up last year by Qualtrics founder Ryan Smith, who owns the NBA’s Utah Jazz and the NHL’s Utah Mammoth, together with his longtime backer Ryan Sweeney, a general partner at Accel.
Portage, Wellington, Crosslink Capital, 53 Stations, Titanium Ventures, Spice and Florida Funders also took part.
Flex says the money brings its total equity raised to $180m, alongside $300m of debt. Headcount stands at 110 and the company expects to be past 200 by the end of the year.
The pitch is unusually narrow, and on Flex’s telling, unclaimed. The company sells what it calls an AI-native private bank for high-net-worth business owners in the middle market, people who are at once a company’s finance department and its wealthiest individual customer.
“Middle-market business owners are one of the most important and underserved customers in finance globally,” said Zaid Rahman, Flex’s founder and chief executive.
He describes clients whose vendors are scattered across the US, Poland and Brazil, and who stack up two or three providers, and the fees that come with them, simply to pay someone abroad.
Flex puts the US market at roughly 350,000 such owners, responsible for about 40% of private-sector payroll, and the global figure at around 3 million.
Those are the company’s own numbers, and they carry a point about default settings: these owners are multi-entity, multi-currency and multi-jurisdiction whether they meant to be or not.
What Flex Global actually does?
The product launched alongside the round extends the platform past the US border. Flex Global promises stablecoin payment rails in more than 100 countries, multi-currency accounts across 76 countries covering 32 currencies, institutional dollar accounts for foreign owners, private credit in more than 20 countries, and cards issued across entities and geographies on one platform.
Cross-border payments settle in minutes rather than days, according to the company. The stablecoin layer is meant to stay out of sight: an owner paying a supplier in Warsaw pays them the way they would pay one in Dallas, and never touches a wallet.
That bet on invisibility depends on rails that only recently became usable. Visa’s settlement pilot reached a $7bn annualised run rate in April, up by half on the previous quarter, and research by Artemis and McKinsey found that genuine stablecoin payment volume roughly doubled in 2025 to about $390bn, most of it business-to-business.
Incumbents noticed at about the same time. Mastercard’s $1.8bn purchase of BVNK was the clearest signal yet that the technology had graduated from pilot to plumbing, while banks argue publicly over which AI races decide the next decade.
Flex says annualised payment volume has crossed $10bn, growing roughly fourfold year on year on a nine-figure revenue run rate, with revenue up threefold since December.
Its biggest customer categories by logo count are construction, wholesale and multinational businesses.
Smith, who came in as a strategic investor, framed the gap in the terms he knows best.
“I’ve spent my career helping entrepreneurs win, and they all have the same problem: their business and personal financial lives are completely intertwined, but every bank treats them as two different customers,” he said.
What Halo brings beyond the cheque is distribution. Its remit runs across the NBA, the NHL and Formula 1, an odd sales channel for a bank until you remember that Flex’s customers were never in Silicon Valley’s address book to begin with.
The platform already bundles credit, banking, payment processing, bill pay, expense management, treasury and a set of finance agents, including one called Beacon AI, into what Flex calls an agentic back office.
That puts it in the same emerging category as agentic banking platforms built to let software, not people, move the money. Next on the roadmap: personal credit and rewards cards, treasury, travel, and mortgages. Whether the owner of a mid-sized construction firm wants their bank to book their flights is a question the next round will presumably answer.
Get the TNW newsletter #
Get the most important tech news in your inbox each week.