❯ AI finance software company Rillet raises $100 million Series C at $1 billion valuation

LEDGERAI-native ERP company Rillet has raised a $100 million Series C at a $1 billion valuation, led by ICONIQ. It rewrote the corporate general ledger: transaction data streams into the books in real time via native integrations, and AI agents handle reconciliation and journal entries directly in the ledger, while humans retain approval rights and every change leaves an audit trail. The company came out of stealth in 2024 and now has more than 600 customers, including public companies.

PACEThis is Rillet’s third financing round in fourteen months, with cumulative funding surpassing $200 million. The pace is that tight because demand is moving faster than product iteration: net new annual recurring revenue doubled in the past three months. It replaces legacy systems such as Oracle Fusion, SAP, Workday, Microsoft Great Plains, and NetSuite — and the spreadsheets and plugins that grew up around them. Most of these systems are based on architecture from ten to twenty years ago: data lives in one place, work happens in another, and the two sides are only reconciled at month-end close. AI agents cannot enter that structure; they can only attach to the outside as assistants. Rillet’s approach is to replace the ledger itself, giving agents a place to stand. Disclosed customers include Mercor, Function Health, and Temporal.

DISPLACEMENTThe pitch centers on closing the books. Traditional finance teams spend one to two weeks per month on month-end close. Rillet argues for continuous close: data flows into the ledger in real time, current-period numbers are available at any time, and the concentrated month-end cycle is flattened out. Founder and CEO Nicolas Kopp puts it this way: “Financial agents need more than just access to data; they need to work inside the general ledger.” He predicts that within two or three years every company will run finance this way. The moat is switching costs — ERP is one of the hardest systems in a company to replace, and once the general ledger moves over, audit, tax, and consolidated reporting all follow. Renewal is almost the default option. That also explains why Sequoia, a16z, Bain Capital Ventures, Oak HC/FT, Battery Ventures, FirstMark, Scale Venture Partners, and Creandum invested three rounds in a row within a year: the bet is on capturing the installation window, because the ERP layer gets replaced once per generation.

SHIFTA $1 billion valuation is not expensive by ERP standards — NetSuite was acquired by Oracle for $9.3 billion back then. Capital is pricing whether AI can get into core systems: over the past two years, enterprise AI spending has mostly gone to edge use cases — customer service, documents, code completion — where failures have manageable impact. The general ledger is another matter: one wrong entry leaves a mark in the audit report. Rillet getting a $1 billion valuation means the market accepts that AI agents can operate inside audited systems, as long as approvals and audit trails are properly in place. The pressure is on companies that build plug-ins on top of old ERPs — their position rests on the assumption that legacy systems cannot be replaced, and that assumption is loosening.

▪ SIGNALEnterprise AI money is moving from edge use cases into audited core systems. A general-ledger generation change locks in a decade.