Basis AI Hits $1.15B Unicorn — Used by 30% of Top 25 US Accounting Firms, First Agent to Autonomously Complete Partnership Tax Returns

Bloomberg·high signal

AI-for-accounting startup Basis raised $100M at a $1.15B valuation led by Accel with GV and former Goldman Sachs CEO Lloyd Blankfein, reaching unicorn status. The company is now used by 30% of the top 25 and 20% of the top 150 US accounting firms. Basis recently demonstrated the first AI agent to autonomously complete an entire end-to-end Form 1065 partnership tax return. Their core differentiator: 'long-horizon agents' designed to work on complex tasks for hours or days, not just answer prompts. Total raised: $138M. Meanwhile, predecessor Botkeeper has shut down — unicorns and funerals in the same accounting AI category.