U.S. AI Startups in 2025: 33 Companies That Have Raised $100M+

Record-Breaking Momentum in AI Funding

Artificial intelligence (AI) investment in the United States continues at a remarkable pace. In 2024, 49 startups secured rounds of $100 million or more, according to TechCrunch. That included three companies with multiple “mega-rounds” and seven firms landing investments of $1 billion or greater.

With just a few weeks left in Q3 2025, the momentum shows no signs of slowing. This year has already seen several billion-dollar raises, alongside multiple repeat mega-rounds, suggesting investor appetite remains strong.

Below is a month-by-month look at U.S. AI startups that have raised $100 million or more in 2025.

August 2025: Healthcare and Research in Focus

• EliseAI – The healthcare and housing automation platform raised $250 million in a Series E, announced August 20. The round, led by Andreessen Horowitz, placed the company’s valuation at $2.2 billion.

• Decart – An AI research lab, Decart secured $100 million at a $3.1 billion valuation on August 7. Investors included Sequoia Capital, Benchmark, and Zeev Ventures.

July 2025: Mega-Rounds Dominate

• Fal – A generative media platform, Fal announced a $125 million Series C on July 31. Led by Meritech Capital Partners, the round valued the company at $1.5 billion. Other backers included Salesforce Ventures, Shopify Ventures, and Google AI Futures Fund.

• Ambience Healthcare – This five-year-old startup raised $243 million in a Series C, led by Oak HC/FT and Andreessen Horowitz. Investors included Kleiner Perkins, OpenAI Startup Fund, and Smash Capital.

• Reka AI – The research-focused firm secured $110 million in Series B funding on July 22, valuing the company at $1 billion. Backers included Snowflake and Nvidia.

• Thinking Machines Lab – Announced one of the largest rounds of the year: $2 billion in seed funding on July 15. The round, led by Andreessen Horowitz, also included Nvidia, Accel, and AMD, pushing its valuation to $12 billion.

• OpenEvidence – Based in Cambridge, Massachusetts, OpenEvidence raised $210 million in Series B funding, announced July 15. Led by Kleiner Perkins and GV, the company is now valued at $3.5 billion.

• Harmonic – Developer of a mathematical reasoning engine, Harmonic raised $100 million in a Series B, announced July 10. Kleiner Perkins led the round, giving the company a valuation of $875 million.

June 2025: AI in Healthcare, Law, and Enterprise

• Abridge – This healthcare AI unicorn raised $300 million in a Series E, its second funding round of 2025. The June round, led by Andreessen Horowitz and Khosla Ventures, valued Abridge at $5.3 billion.

• Harvey – Specializing in AI tools for legal services, Harvey raised another $300 million (Series E) on June 23, co-led by Kleiner Perkins and Coatue. The round brought Harvey’s valuation to $5 billion.

• Tennr – A healthcare AI startup, Tennr secured $101 million in Series C funding, valuing the company at $605 million. The round was led by IVP, with participation from Lightspeed, GV, and Andreessen Horowitz.

• Glean – Enterprise search platform Glean announced a $150 million Series F, led by Wellington Management. The company is now valued at $7.25 billion.

• Anysphere – The AI research lab behind coding tool Cursor raised $900 million in Series C funding, led by Thrive Capital with backing from Andreessen Horowitz, Accel, and DST Global, valuing the company near $10 billion.

May 2025: Infrastructure and Benchmarking Gains

• Snorkel AI – The data labeling platform raised $100 million in Series D funding on May 29, at a valuation of $1.3 billion. Addition led the round.

• LMArena – Known for its benchmarking tools for AI models, LMArena secured a $100 million seed round on May 21. The round, co-led by Andreessen Horowitz and UC Investments, valued the startup at $600 million.

• TensorWave – The Las Vegas-based infrastructure firm raised $100 million in Series A funding on May 14, co-led by Magnetar Capital and AMD Ventures.

April 2025: Model Development at Scale

• SandboxAQ – Closed a $450 million Series E on April 4, with backing from Nvidia, Google, and Ray Dalio, valuing the firm at $5.7 billion.

• Runway – The AI media production platform announced a $308 million Series D on April 3, led by General Atlantic, valuing the company at $3 billion.

March 2025: Landmark $40B Round

• OpenAI – Closed the largest round of the year so far, a $40 billion funding raise, valuing the company at $300 billion. The March 31 round was led by SoftBank with backing from Thrive Capital, Microsoft, and Coatue.

• Nexthop AI – Raised $110 million in Series A funding on March 25, led by Lightspeed Venture Partners.

• Insilico Medicine – Secured $110 million in Series E funding on March 13, valuing the biotech company at $1 billion.

• Celestial AI – Raised $250 million in Series C funding, announced March 11, at a valuation of $2.5 billion.

• Lila Sciences – Closed a $200 million seed round to develop a science superintelligence platform.

• Reflection.Ai – The Brooklyn-based startup raised $130 million in Series A funding, valuing the company at $580 million.

• Turing – The AI coding firm raised $111 million in Series E funding, with a valuation of $2.2 billion.

• Shield AI – Secured $240 million in Series F funding, co-led by L3Harris Technologies and Hanwha Aerospace, with a valuation of $5.3 billion.

• Anthropic – Announced a $3.5 billion Series E on March 3, valuing the company at $61.5 billion.

February 2025: Infrastructure Push

• Together AI – Raised $305 million in Series B funding, valuing the company at $3.3 billion.

• Lambda – Closed a $480 million Series D on February 19, at a valuation near $2.5 billion.

• Abridge – Earlier in February, Abridge raised $250 million in Series D funding, at a $2.75 billion valuation.

• Eudia – The AI legal tech company raised $105 million in Series A funding on February 13.

• EnCharge AI – Announced a $100 million Series B round on February 13, backed by Tiger Global and Samsung Ventures.

• Harvey – Raised a $300 million Series D on February 12, valuing the company at $3 billion.

January 2025: Healthcare and Voice AI

• ElevenLabs – The synthetic voice platform raised $180 million in Series C funding, announced January 30, with a valuation above $3 billion.

• Hippocratic AI – Raised $141 million in Series B funding on January 9, led by Kleiner Perkins, with a valuation above $1.6 billion.

Conclusion

From mega-rounds like OpenAI’s $40 billion raise to early-stage breakthroughs such as LMArena’s $100 million seed round, U.S. AI startups are attracting unprecedented investor confidence in 2025. With billions flowing into healthcare, infrastructure, legal tech, and generative AI, the sector’s trajectory appears set for continued acceleration.

Author: Din Kumar