The numbers come first. Rillet, a startup building what it describes as the first AI-native accounting platform, has closed a $100 million Series C at a $1 billion valuation, the company told Fortune exclusively. The round was led by ICONIQ, with participation from returning investors Sequoia Capital, Andreessen Horowitz and Oak HC/FT, and new backers including Bain Capital Ventures, Sequoia Global Equities, Battery Ventures, FirstMark, Scale Venture Partners and Creandum. ICONIQ general partner Seth Pierrepont is joining Rillet's board.
The raise pushes Rillet's total funding past $200 million and marks its third fundraise in the past year — an unusually compressed capital formation timeline even by Silicon Valley standards.
From spreadsheets to agents. Co-founder and CEO Nicolas Kopp, who has a finance and accounting background, framed the company's mission in blunt terms: give CFOs their weekends back. 'CFOs really struggle day to day. They can't see their families on weekends,' Kopp told Fortune, pointing to the hours finance chiefs spend reviewing data and building presentations. His answer is an 'agent-first' architecture — AI systems capable of running hundreds of operations in parallel, replacing the manual data-entry workflows that traditional enterprise resource planning software was designed around.
Kopp was equally direct about the labor question. 'Our message is not that we're coming after jobs. That's just not correct,' he said, positioning AI as a productivity multiplier for finance professionals rather than a replacement. 'Domain expertise' is core to the company's mission, he added.
Customer traction across sectors. Rillet now serves more than 600 customers, including Neuralink, Skild AI and Mercor. The company says Mercor's three-person finance team is using Rillet's AI agents to manage a business scaling past $2 billion in annual recurring revenue. Roughly 40% of Rillet's customer base now sits outside the tech and AI sectors, spanning industries Kopp described as ranging from waste recycling to movie studios — evidence, he argued, that AI-native finance tools are crossing into the broader U.S. economy.
New annual recurring revenue doubled quarter over quarter after the Series B, and doubled again in the three months leading into this latest raise.
The legacy target. Rillet's competitive pitch names names: Oracle Fusion, SAP, Workday, Microsoft's Great Plains and NetSuite are all described as pre-AI architectures vulnerable to displacement. 'Some of these giants that seemed untouchable' are now facing serious disruption, Kopp said, as enterprise customers move to replace legacy systems. The core architectural distinction, he argued, is that traditional ERP platforms were designed for human data entry, while Rillet is built for AI agents to execute complex, end-to-end accounting work and generate a complete audit trail. 'Proving out the work layer is mission-critical for enterprise readiness,' Kopp said.
Pierrepont echoed the thesis in a press release: 'What stands out is how customers actually run on it — multibillion-dollar businesses operating with finance teams a tenth the traditional size, closing their books continuously.'
CEO Times take. Rillet's trajectory is a clean case study in what happens when free enterprise meets genuine technological disruption: capital moves fast, incumbents feel the pressure and the customer — in this case the CFO buried in spreadsheets — wins. The real story here is not the unicorn badge; it is that a two-year-old company with a focused product and a credible founding team has already forced a conversation about the relevance of software empires built over decades. When the market votes this quickly and this decisively, legacy vendors should be paying attention.
