The Story
From Dubai Dust
to Digital Banking
The Invoice That Started Everything
Construction is a business of float. You mobilize capital. You build. You invoice. Then you wait. In Dubai's overheated property market in the 2000s, the wait could stretch from weeks to quarters - and if the client decided to dispute, you were exposed. Zaid Rahman watched his father navigate exactly that exposure at close range. One client. One refused multimillion-dollar invoice. One health crisis that followed.
The numbers that appear in the rest of Zaid's career - $490M raised, $3B in payments volume, a Series B in December 2025 - all trace back to that single point of failure. Not a pivot. Not a pivot from something generic. A response to something specific, personal, and structurally wrong.
The Thiel Bet
Columbia University accepted him. The Thiel Fellowship accepted him too - with one condition: no college. Peter Thiel's fellowship, now one of the most selective programs in technology entrepreneurship, has produced a cohort of founders who collectively built some of the defining companies of the past decade. Zaid's class graduated in 2017.
His family pushed back. The idea of skipping an Ivy League degree for a startup program was not immediately obvious from the UAE, where academic credentials carry significant social weight. But Zaid's parents came around - and the track record since has been hard to argue with.
Two Exits Before Flex
Pilot Labs came first: a K-12 and university-focused EdTech platform built around software for educational institutions. It was acquired by a private equity firm - a quiet exit, but an exit nonetheless. The discipline to build something acquirable, then move on to the next problem, is not common at 22.
Volley was bigger in ambition. An AI knowledge management company that worked with Fortune 500 enterprises, helping organizations synthesize institutional knowledge from unstructured information using natural language processing. Before ChatGPT made this a household category, Volley was doing it quietly for the kinds of companies that measure software contracts in the millions. JPMorgan Chase backed it. So did Zuckerberg Ventures - Mark Zuckerberg's personal investment vehicle, distinct from Meta's corporate activity.
Both exits funded something more important: credibility. By the time Zaid started talking to investors about Flex, he wasn't a first-time founder with a pitch deck. He was someone who had sold one company, grown another with enterprise validation, and built a 100-company angel portfolio on the side.
305 Ventures and The City Before San Francisco
Miami had a moment in 2020. When Francis Suarez started tweeting at founders and the pandemic made geography optional, a community coalesced in the 305. Zaid was there early. He co-founded The305 - a networking group that reached 1,000 active members - and alongside it, 305 Ventures, an angel fund with over 100 investments across fintech, Web3, DeFi, and enterprise software. The '305' is Miami's area code. The community was real. And it gave Zaid a network that would later seed Flex's early growth before the company relocated its operational center to San Francisco.
Building Flex
In 2022, Zaid co-founded Flex with Hadi Solh. The initial thesis: mid-market business owners - companies doing $3M to $100M in annual revenue - were the most underserved segment in American financial services. They were too large for consumer banking apps. Too small and too complex for the enterprise banking system. And the tools that existed for them - credit cards, payroll, AP software, banking - were separate products that never talked to each other.
Flex was designed to be the one platform that saw all of it: from the moment revenue arrived, through bill payments, payroll, expense management, cashflow analytics, and all the way to personal spending for the business owner's household. One login. One intelligence layer. One financial operating system.
The Series A raised $120M in equity and debt, led by Florida Funders with participation from Home Depot Ventures. Then in March 2025, Flex raised another $225M at a $250M valuation. By that point, the company had achieved a milestone almost no fintech reaches in its first two years: $1 billion in annualized total payments volume, 18 months after launching its core card and bill pay products.
The Visa Infinite Card
The product that put Flex on the map for mid-market owners wasn't an algorithm or an AI dashboard. It was a card. Specifically: the first Visa Infinite Business credit card ever issued by a US fintech. Visa Infinite is the tier above Visa Signature - the tier historically reserved for ultra-premium personal products available only at the largest banks. Unlimited 1.75% cashback. 60 days interest-free on every purchase. Access to 1,300 airport lounges. A 24/7 concierge. No annual fee. No caps. No category restrictions.
For a business owner running a $20M logistics company, the ability to put operating expenses on a card with 60-day float, earn uncapped cashback on every transaction, and access Priority Pass lounges on business trips - without paying a $550 annual fee - is genuinely novel. No one had built it before because no one had focused deeply enough on this customer to know they needed it.
Acquiring Maza
In April 2025, Flex acquired Maza - an a16z-backed consumer fintech with a focus on Spanish-speaking users - for $40M. Ninety-five percent of Maza's 22-person team joined Flex. An additional $10M equity injection funded the new Flex Consumer unit. The acquisition gave Flex something most B2B fintechs never build: a direct consumer relationship that can follow business owners from their corporate finances into their personal accounts. The same owner who runs their $15M distribution company through Flex Business can now run their household finances through Flex Consumer. That's the super app thesis made concrete.
December 2025: The Series B
The Series B closed at $60M in December 2025, led by Portage Ventures with participation from Titanium Ventures, Wellington, and Crosslink Capital. Total equity raised crossed $105M. Total funding across debt and equity reached $490.5M. The company had 140 employees, $150M in annual revenue, and an annualized payments volume of $3B - triple where it had been twelve months earlier. Revenue had quadrupled year-over-year.
Zaid framed the round not as a celebration but as a platform. The pitch to investors wasn't that Flex had arrived. It was that the mid-market had arrived as a category - and Flex was first.
