How AI accounting startup Rillet raised $100M and became a unicorn in 48-hours

Rillet secured $100 million at a $1 billion valuation within 48 hours, adding to its prior $200 million raise from investors including Iconiq, Andreessen Horowitz and Sequoia. The AI-native accounting platform now serves 600 customers, doubled its annualized revenue growth last quarter, and partnered with EY. Its architecture lets users choose foundational models such as OpenAI or Anthropic, isolates data to prevent cross-training, and logs every AI-driven accounting decision for auditability.