Heidi raises $340 million at $900 million valuation for healthcare AI

Heidi, a clinical-documentation AI startup, has raised $340 million in new financing at a $900 million valuation, roughly double the $465 million valuation it held after its Series B round in October 2025.

The money comes in two forms. A $100 million Series C round is led by Blackbird, which has held a stake in Heidi since its pre-seed round in 2021, with participation from Phoenix Court, Point72 Private Investments and Headline. The remaining $240 million comes from General Catalyst’s Customer Value Fund, a non-equity financing vehicle: General Catalyst takes no equity stake or warrants in exchange for the capital. The fund instead finances Heidi’s sales and marketing spend and is repaid through a combination of principal repayment and revenue participation capped at a set return, which makes it function closer to a loan than a traditional venture investment.

With the new round, Heidi’s total funding reaches $436.6 million since its founding. Heidi said its annual recurring revenue grew from $1 million to $50 million over two years, reaching the $50 million mark in April. The company also reported that the number of patient visits its software supports rose from 73 million to 175 million, alongside more than 67 million clinical hours logged, about 2.8 million weekly patient interactions across 110 languages and 190 countries, a 62% enterprise activation rate, and roughly 600 employees. These figures are company-reported and have not been independently verified.

Heidi’s raise sits alongside a string of large 2026 AI financings. Forus raised $150 million in a Series C at a $3 billion valuation, and Francisco Partners agreed to acquire healthcare AI platform Weave Communications for about $650 million. River AI raised $1.1 billion in combined seed and Series A funding in August 2026.

“From the day I started Heidi, the ambition was always bigger than writing doctor’s notes,” said Dr. Thomas Kelly.

New product capabilities tied to the raise will not be available in the UK and EU markets, with no timeline or rationale given for the restriction.