San Francisco-based Rime raises $24 million led by M13 to scale its linguistics-first speech-to-speech voice AI platform, already handling nearly 100 million calls monthly for Mayo Clinic and Dialpad — and hires ex-Meta audio research lead Rafael Valle as Chief Science Officer.
On July 15, 2026, San Francisco-based voice AI startup Rime announced a $24 million Series A funding round led by M13, with participation from Twilio Ventures, Corazon Capital, Unusual Ventures, and Cadenza Ventures. M13 Partner Morgan Blumberg joins Rime's board of directors. The round follows a $5.5 million seed raised in May 2025, bringing total funding to approximately $30 million as the company scales its enterprise speech-to-speech platform.
Founded in 2022 by Lily Clifford (CEO), Brooke Larson (an ex-Amazon Alexa linguist), and Ares Geovanis (a Stanford engineer), Rime takes a linguistics-first approach to voice AI that sets it apart from competitors who rely primarily on scraped or synthetic audio data. The company operates its own recording studio in San Francisco to collect proprietary conversational speech data, which it uses to train models that handle the full complexity of real-world phone calls — interruptions, accents, background noise, and domain-specific vocabulary — rather than simple command-and-response patterns. Rime's models now power nearly 100 million phone calls per month for enterprise customers, with particular strength in regulated industries including healthcare and financial services.
Alongside the funding, Rime appointed Rafael Valle as Chief Science Officer. Valle previously led audio research at Meta's Super Intelligence Lab and worked on neural audio synthesis at NVIDIA — two of the most prominent research groups behind modern TTS and voice cloning technology. His hire signals Rime's ambition to push beyond the current voice AI quality ceiling, with a focus on reducing latency in speech-to-speech models while improving emotional range and conversational naturalness. The company, currently at around 35 employees, plans to use the new capital to expand its proprietary multilingual conversational dataset, hire engineering and research talent, and scale infrastructure.
The round reflects a broader acceleration in enterprise voice AI funding. More than $7 billion flowed into voice AI startups in the first quarter of 2026 alone, and the global market is projected to exceed $20 billion by 2031, growing at a compound annual rate above 30%. Rime's linguistics-first, data-sovereign approach — collecting its own training data rather than relying on web-scraped audio — positions it as a differentiated player in a market where model quality, regulatory compliance, and auditability increasingly determine enterprise procurement decisions.
