Flex raises $70M led by Halo Fund for AI-native private banking

In an environment where financial innovation usually orbits around digital startups or big tech, a company has managed to attract the attention of top-tier investors with a proposal that breaks traditional molds: to become the native private bank in artificial intelligence for owners of medium-sized companies. Flex, the San Francisco-based company, has closed a $70 million Series B1 round led by Halo Fund, Ryan Smith and Ryan Sweeney's vehicle, with participation from Portage, Wellington, Crosslink Capital and others. The reported valuation of about $1.2 billion is double what the company had just six months ago, an unmistakable sign that the market is recognizing a new paradigm in corporate financial management.

The interesting thing about this operation lies not only in the figure, but in the thesis that supports it. Flex does not promise to make accounting reconciliation faster or more efficient for a payable accounts department. Its goal is much more ambitious: to become the only institution with which the owner of a medium-sized company operates both the business and personal sides of his balance sheet. That is, to unify on the same platform what is currently fragmented between a regional bank, a card issuer, a currency broker, a wealth manager and a lender. And to do so, in addition, with an architecture based on artificial intelligence that allows data from both worlds to be cross-referenced to make credit, treasury and investment decisions in real time.

To understand the magnitude of this proposal, it is worth looking at the figures handled by the market it is aimed at. There are approximately 200,000 middle-market companies in the United States that employ 48 million people and generate a third of private GDP. Flex estimates that it serves a universe of between 350,000 and 400,000 owners in the country alone, and about three million globally. However, this segment has historically been ignored by fintech. While large corporations have dedicated treasury desks and consumers have mobile banking apps, the owner of a medium-sized company often resorts to an artisanal mix of tools: an Excel, a regional bank, an American Express card and, if he's lucky, a wealth manager who barely knows the workings of the business. Flex aims to be the glue that binds all those dots together.

The hidden opportunity in cross-border payments

One of the strategic focuses of Flex Global, the new layer of international payments that the company is launching along with this round, is cross-border settlement using stablecoins. The argument is overwhelming: traditional banks charge between 2% and 5% of the value of an international transfer when you add up the exchange rate margin, correspondent fees and hidden deductions. Specialized fintechs reduce it to 0.3-0.8%. And a stablecoin-based rail can trade between five and fifteen basis points. The difference is not marginal: for a company that moves $10 million a year abroad, moving from a bank to a stablecoin system can save hundreds of thousands of dollars annually.

But Flex doesn't just offer a paid rail. The company integrates this rail within a platform that already includes business credit cards with 60 days of interest-free financing, expense management, payments to suppliers, automation of accounts payable, treasury, working capital and, finally, private credit. And all this under the same interface that knows both the company's account and that of the owner's home. That holistic view is what has enabled the average Flex customer to use four or more products on the platform, a metric that most fintechs take a decade to achieve and that Flex has achieved in three years.

Artificial intelligence at the core, not the ornament

In a market where any financial platform claims to have artificial intelligence, Flex differs not by the model, but by the data on which it is trained. By having simultaneous access to the company's ledger and the owner's personal balance sheet, the company generates a unique corpus of credit information. There is no comparable database in the public market, as banks have never organized their information in this way. This proprietary corpus allows Flex to underwrite loans and lines of credit with a level of accuracy that its competitors can't replicate, because they simply don't see both halves of the balance sheet.

The practical application of this artificial intelligence is materialized in AI agents that manage underwriting, treasury management and reconciliation autonomously. These are not conversational assistants, but engines that make decisions in real time based on historical patterns and in real time. For example, if an owner receives an unexpected payment from a customer, the system can automatically suggest the best way to apply it: reduce a debt, invest in a time deposit or leave it as a liquidity buffer. All without human intervention. This capability is especially valuable for companies that lack a dedicated CFO, which is precisely the majority of mid-market SMEs.

Fitting in with technological and business trends

Flex's round comes at a time when the fintech industry is redefining its priorities. After years of massive investment in expense management solutions for startups (such as Ramp or Brex) or international payment platforms (such as Airwallex), investors are looking for models that offer higher margins and lower customer churn. Flex fits perfectly into this search: its implicit take rate is between 1% and 2.5% of the volume processed, compared to 0.45% for Airwallex or 0.26% for Mercury. That difference is not accidental, but structural: Flex earns through the card interchange fee, the net interest margin on deposits and the loan spread, all applied to a customer who uses multiple products.

This approach is reminiscent of the strategy that built Atlassian into an enterprise software giant: instead of selling a single tool, it offers an ecosystem that expands naturally. Flex is doing the same thing, but in the world of finance. Each new product a customer adopts increases the surface area of the relationship without increasing the cost of acquisition, resulting in net revenue retention that few companies can match. And all this leveraged on a robust cloud infrastructure that allows you to scale without losing performance.

Q2BSTUDIO: technology at the service of financial innovation

Behind proposals like Flex's is a development ecosystem that is rarely mentioned, but is critical. The ability to build platforms that integrate multiple financial services, operate on real-time data, and deploy across multiple jurisdictions depends on bespoke applications and a well-designed software architecture. At Q2BSTUDIO we work on just that: we help companies create custom software solutions ranging from the integration of AWS and Azure cloud services to the implementation of artificial intelligence engines capable of processing large volumes of financial data.

Our team has seen firsthand how AI for business can transform processes that were previously manual and expensive. For example, we have developed AI agents that automate bank reconciliation, detect anomalies in cash flows or recommend investment strategies in real time. These systems are supported by power bi dashboards that allow managers to visualize the financial health of their business at a glance. And all this under the highest cybersecurity standards, an essential requirement when handling sensitive customer and transaction data.

The role of stablecoins and regulation

One of the most talked-about aspects of Flex's round is its commitment to stablecoins as a settlement rail. The company has developed a proprietary layer that allows payments to be sent to more than 100 countries with settlement in minutes, using institutional dollar accounts for foreign clients and multi-currency accounts in 76 countries supporting 32 currencies. However, the real value is not in the rail itself, but in what it enables: Flex can now offer international payments at a cost that traditional banks cannot match, and this attracts customers to its platform. Once inside, the company can sell them credit, treasury, and investment products.

However, this strategy is not without regulatory risks. The GENIUS Act, which regulates stablecoins in the United States, was signed into law in July 2025, but the implementation rules are not yet finalized. Flex operates in a framework that is still under development, which introduces uncertainty that investors will need to monitor. However, the management team has argued that waiting for full regulatory clarity would mean losing 12 to 18 months of competitive advantage. In a market where B2B stablecoin payments are growing 733% year-over-year, the risk of not moving may be greater than moving before the rules are fully defined.

Lessons for entrepreneurs and CTOs

The case of Flex offers several lessons applicable to any technology project looking to scale in a regulated sector. The first is the importance of building a proprietary data core. Flex is not competing for the best AI model, but for having the most relevant data. This can only be achieved by integrating sources that no one else integrates, such as the company's balance sheet and the owner's own staff. The second lesson is that monetization should not depend on a single product. The more services a customer uses, the harder it is for them to leave. The third is that the infrastructure must be flexible and scalable, capable of operating in multiple countries and with different regulatory frameworks without losing performance.

For companies that want to follow this path, having specialized technology partners makes all the difference. At Q2BSTUDIO we offer business intelligence and platform development services that integrate multiple data sources, automate processes and guarantee information security. If your company is considering launching a financial product, or simply wants to optimize its operations with artificial intelligence, we can help you design and implement the most appropriate solution. Innovation is not just about ideas, but about technical execution, and that's where our team can add value.

Conclusion: A New Standard for Business Banking

Flex has achieved something that seemed impossible: raise 70 million dollars with a thesis that does not promise productivity, but ownership of the client's entire financial relationship. The 1,200 million valuation reflects that the market believes in this vision, but the real challenge lies ahead: to demonstrate that the model can scale internationally without losing the margin per customer. If it succeeds, Flex will not only have built a valuable company, but will have redefined what it means to be a private bank in the digital age. And for those of us who observe from technology, it is a reminder that the best opportunities are usually where the big players do not look: in the space between the invoice and the payment, between the company and the home, between the data that already exists and that no one has been able to put together.