Flex, a San Francisco-based AI-native private banking platform for high-net-worth business owners in the middle market, has raised a $70 million Series B1 led by Halo Fund, the investment platform co-founded by Utah Jazz and Utah Mammoth owner and Qualtrics founder Ryan Smith and Accel general partner Ryan Sweeney. Portage Ventures, Wellington, Crosslink Capital, 53 Stations, Titanium Ventures, Spice, Florida Funders, and others also participated. The round comes just months after Flex’s $60 million Series B in December 2025 and brings total equity raised to $180 million and total capital, including debt, to $300 million. Annualized revenue has grown 3x since the December round, and Flex is now at a nine-figure annualized revenue run rate with more than $10 billion in annualized total payment volume, growing roughly 4x year over year.

Flex was launched in 2023 around a thesis that Silicon Valley fintech built tools for consumers and for venture-backed startups but largely missed the high-net-worth business owner—someone who operates across multiple entities, currencies and jurisdictions and whose business and personal financial lives are deeply intertwined. In the US alone, roughly 350,000 such owners help drive 40% of private-sector payroll; globally, an estimated 3 million sit at the center of a meaningful share of private economic activity. Flex’s platform is built as a unified private banking relationship for that customer, spanning private credit, business finance, personal finance, payments and an agentic back-office finance operating system under one roof. The average Flex customer now uses four or more products on the platform, reflecting the compounding relationship the company is designed to create. Flex’s three largest business categories by logo count are construction, wholesale and multinational businesses.

The centerpiece of the Series B1 announcement is the launch of Flex Global, an international expansion of the platform designed to serve business owners who operate across borders, currencies and regulatory jurisdictions as a matter of course. Flex Global includes stablecoin payment rails and wallets in more than 100 countries settling cross-border payments in minutes; institutional USD accounts for foreign business owners who need access to the world’s reserve currency; multi-currency accounts across 76 countries supporting 32 currencies from USD to RMB, INR and MXN; private credit solutions in more than 20 countries; and cards issued to businesses spanning entities and geographies under one platform. Critically, Flex’s model is designed to make the underlying stablecoin rails invisible to the end user: an owner pays a vendor in Warsaw or Mexico City the same way they would pay one in Dallas, with AI helping them make decisions across their full balance sheet without ever touching a wallet.

Halo Fund’s strategic value to Flex goes beyond capital. The fund’s platform spans the NBA, NHL and Formula 1, giving Flex distribution access to audiences of successful middle-market business owners and entrepreneurs across communities well beyond Silicon Valley—exactly the customer base Flex Global is built to serve. Smith, as lead investor, brings direct experience as an entrepreneur whose own financial life as a business owner, sports franchise operator and technology company founder straddles exactly the personal-business boundary Flex is designed to collapse.

With the new funding, Flex plans to double its team from 110 employees to more than 200 by year-end and continue expanding its global banking, personal credit and rewards cards, treasury, travel and mortgage offerings. The company’s Beacon AI agentic finance system, which helps owners manage decisions across their entire balance sheet, will also be deepened as Flex builds out the “agentic back office” pillar of its five-part platform strategy.

KEY QUOTES:

“Middle-market business owners are one of the most important and underserved customers in finance globally. Depending on the type of owner, they’ll tell you their vendors are spread across the US, Poland, Brazil, etc; their accounts hold currency outside of just USD; and they have to oscillate across 2-3 vendors and layers of fees just to do business outside their country.”

Zaid Rahman, CEO and Founder, Flex

“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, missing what they’re actually trying to build. Flex is the first team creating a real private bank around the owner and the entire household’s finances, and the gap they’re filling is just as real globally as it is in the US. Zaid and the team have built an enduring business that is becoming an institution for the world’s most ambitious owners.”

Ryan Smith, Co-Founder, Halo Fund and Owner, Utah Jazz and Utah Mammoth