Moving money between businesses has historically been a slow, high-friction process vulnerable to fraud. As these transactions increasingly shift toward instant settlements and AI-powered software, that risk is even higher. Startup GrailPay is tackling these challenges, and Thursday the New York-based fintech said it raised $10.5 million in Series A funding to expand its risk-detection infrastructure.
This latest financing brings GrailPay’s total funding to $17.2 million, marking a “significant” step-up in valuation from its June 2025 seed round, according to co-founder and CEO Will Messina.
MissionOG led the round, which included participation from EJF Ventures, Counterpart Ventures, Eleanor Park Ventures, Construct Capital, Commerce Ventures, and SSC Venture Partners.
From Consumer App to B2B Pivot
The idea for GrailPay began while Messina was a student at Boston College, driven by a simple observation about student budgets.
“I was broke as a college kid, and I used my debit card for everything," Messina recalled in an exclusive interview with This Week in Fintech. "I was like, 'Hmm, why is the person behind me getting 2% with their Amex? I don't really get any points when I go pay for things.’ ”
“And so I thought, I want to stick it to the man and bypass the whole system,’ and have people pay with their bank account when they buy things online,” he added.
While consumers haven’t exactly been eager to buy everyday items directly from their bank accounts, Messina’s curiosity led him to keep studying how the plumbing of the financial system works. He focused on GrailPay full-time upon graduating in 2022. As the company pitched its bank-payment idea to e-commerce merchants, it consistently found a much larger, more systemic challenge on the business-to-business side: While consumer financial apps have advanced rapidly, B2B payments have lagged.
Every day, businesses still rely heavily on wires, paper checks, and standard Automated Clearing House (ACH) transactions — systems prone to severe vulnerabilities.
“On the B2B side, we have all these payments going over wires and ACH and checks, and the experience isn't fun," Messina noted. “There are payments that fail a lot. There's a ton of fraud."
Add to those issues, verifying who is on the other end of a transaction has become increasingly difficult with the rise of sophisticated AI phishing.
Underwriting Risk in an Instant Settlement World
GrailPay’s approach addresses two major trends reshaping business payments: the growing demand for instant transfers and the rise of automated AI software handling corporate cash.
Traditional bank transfers usually take a few days to clear, giving businesses a small window to catch fraud or reverse a mistake. Instant payments don't have that cushion. Once the money leaves, it is gone permanently. To manage that risk, GrailPay set up its own payment processing system to study exactly how and why business transactions fail.
Today, GrailPay leverages that data through its primary product, Account Intelligence. When a business enters a counterparty's account and routing number, GrailPay verifies ownership, checks historical payment reliability, and assesses the risk of moving funds.
This risk assessment relies entirely on proprietary in-house machine learning models. While GrailPay uses generative AI tools for standard marketing and internal workflows, Messina noted that larger enterprise clients are often hesitant to let large language models (LLMs) handle sensitive customer data. Because companies cannot easily control where information goes once it enters a commercial LLM, GrailPay uses dedicated machine learning models in an effort to maintain strict data privacy.
Mission OG Partner Kevin Leonard believes the risk infrastructure for B2B bank payments is a generation behind cards.
“The best options available today are static account verification tools that tell you an account is open, but nothing about what it's done or what it's likely to do next,” he wrote via email. “That was manageable when the rails were slow, and you had days to catch a bad payment before it settled. But real-time payments, agentic commerce, and competitive pressure to fund instantly are all accelerating, and that gap is becoming untenable.”
In his view, GrailPay took a more difficult, yet more effective, route: starting as a processor to generate proprietary outcome data, augmented with third-party signals, to build a risk engine “that gets smarter with every transaction.”
Revenue Growth More Than Doubled
This data-focused strategy has fueled a period of growth for the company. GrailPay is currently approaching $5 billion in annualized payment volume, representing a 20-fold increase since this time last year, according to Messina. At the same time, the company's revenue has grown over 2.5 times since the beginning of this year alone.
Today, GrailPay serves about 30 mid-market and enterprise customers, including banktech platforms, financial institutions, and fintechs. The company claims it has experienced zero customer churn to date. The company has 17 employees, including 13 domestic employees and 4 full-time offshore engineers.
GrailPay plans to use its fresh capital to scale its sales and growth marketing teams, with a heavy focus on education-based “go-to-market.” On the product side, the company is moving past bank account verification into full transaction decisioning, incorporating credit insights and real-time indicators to predict whether a specific upcoming payment will clear successfully.
Ultimately, Messina aims to clear up the opaque nature of the B2B market by building a definitive identity network for business payments and creating a modern alternative to traditional card networks.
