The artificial intelligence sector demonstrated remarkable resilience and growth throughout 2025, with a significant cohort of American startups securing monumental funding rounds. According to comprehensive data analysis, exactly 55 U.S.-based AI companies raised venture capital rounds of $100 million or more during the year. This trend underscores the continued confidence of investors in AI’s transformative potential across industries, from healthcare and enterprise software to foundational infrastructure and creative tools. The funding environment, while evolving from the previous year’s peak, remained exceptionally robust, funneling tens of billions of dollars into the next generation of AI innovation.
AI Startups 2025: Analyzing the $100M+ Funding Landscape
The 2025 funding landscape for AI startups revealed several critical trends. Firstly, the total number of companies achieving mega-rounds increased from 49 in 2024 to 55 in 2025, indicating a broadening of investment beyond a handful of giants. However, the nature of these rounds shifted. While 2024 saw seven rounds reach or exceed $1 billion, 2025 featured fewer of these colossal single raises. Instead, a notable pattern emerged: eight companies secured multiple funding rounds exceeding $100 million within the same year, a significant jump from just three in 2024. This suggests a strategy of more frequent, substantial capital infusions to accelerate growth in a highly competitive market.
Secondly, the distribution of funding highlighted sector-specific momentum. AI infrastructure companies, crucial for providing the computational backbone for the industry, were particularly prominent. For instance, Cerebras Systems raised a massive $1.1 billion Series G, while Groq secured $750 million for its inference technology. Simultaneously, applied AI in healthcare and enterprise solutions attracted heavy investment, demonstrating a clear path to commercialization and revenue. Companies like Abridge, Hippocratic AI, and Harvey showcased the high value placed on AI solutions for regulated, complex industries like medicine and law.
The Investor Perspective: Who is Backing AI’s Future?
Leading venture capital firms and strategic corporate investors dominated the funding rounds. Firms like Andreessen Horowitz, Lightspeed Venture Partners, Sequoia Capital, and Kleiner Perkins appeared repeatedly across dozens of deals, often participating in multiple rounds for the same company. More importantly, strategic investors from the technology sector played an outsized role. Nvidia, AMD, Google, Microsoft, and Salesforce Ventures were active participants, seeking to align with and support the ecosystem built on their platforms. This blend of financial and strategic capital provides startups not just with money, but also with crucial industry partnerships, validation, and go-to-market advantages.
Monthly Breakdown of Major AI Funding Rounds in 2025
The flow of capital was consistent throughout the year, with every month witnessing at least one major deal. The final quarter was especially active, cementing 2025’s status as a landmark year.
December 2025: The year ended with a series of significant raises. Mythic secured $125 million for power-efficient AI compute, while Unconventional AI stunned the market with a $475 million seed round, valuing the one-year-old foundational computing startup at nearly $4.5 billion. Generative media platform Fal closed its third round of the year, a $140 million Series D.
November 2025: This month featured some of the year’s largest deals. Anysphere, the maker of the Cursor AI coding platform, raised a staggering $2.3 billion. Luma AI, focused on visual media creation, secured $900 million. These rounds highlighted investor appetite for both developer tools and consumer-facing creative applications.
September 2025: A pivotal month that included Anthropic’s record-breaking $13 billion Series F, valuing the AI safety research lab at $183 billion. Other major deals included Cognition AI ($400 million for its Devin coding agent), Sierra ($350 million for customer service AI), and Cerebras Systems’ $1.1 billion infrastructure round.
March 2025: The first quarter peaked with OpenAI’s historic $40 billion round, led by SoftBank, which valued the company at $300 billion. This round alone represented a massive portion of the year’s total AI investment and set a new benchmark for private market valuations in technology.
Sector Spotlight: Where Did the Capital Flow?
The funding data allows for a clear segmentation of investment priorities:
- •AI Infrastructure & Hardware: This foundational layer received enormous sums. Companies like Cerebras, Groq, Lambda, TensorWave, and Celestial AI collectively raised billions to build the next generation of chips, servers, and cloud platforms specifically designed for AI workloads.
- •Healthcare & Biotech AI: A perennial favorite for investors due to its high impact and addressable market. Startups like Hippocratic AI, Abridge, Ambience Healthcare, OpenEvidence, and Insilico Medicine raised over $1.5 billion combined, focusing on everything from clinical documentation and patient interaction to drug discovery.
- •Enterprise & Developer Tools: Tools that help businesses integrate and build with AI saw strong demand. Glean (enterprise search), Harvey (legal AI), Anysphere/Cognition (AI coding), and Distyl AI (enterprise software) all achieved unicorn or decacorn valuations through large funding rounds.
- •Creative & Generative AI: Platforms enabling new forms of content creation continued to attract capital. Runway, Fal, Luma AI, and ElevenLabs (synthetic voice) secured significant funding to advance generative media for professional and consumer use.
- •AI Research Labs: Entities focused on fundamental AI research and large language model development commanded the largest checks. OpenAI, Anthropic, Thinking Machines Lab, and Reka AI raised tens of billions, reflecting the high-stakes race for artificial general intelligence (AGI) capabilities.
The Impact on Valuation and Market Dynamics
The surge in funding naturally propelled valuations to unprecedented levels. The 2025 cohort created numerous new unicorns (startups valued over $1 billion) and several decacorns (valued over $10 billion). This valuation inflation has important implications. It provides these companies with a long runway for ambitious, often capital-intensive research and development without immediate pressure for profitability. However, it also raises the stakes for future exit opportunities, whether through IPOs or acquisitions, and increases scrutiny on their ability to generate sustainable revenue. The high valuations also intensify competition for talent and resources within the AI ecosystem.
Conclusion
The story of AI startups in 2025 is one of sustained, strategic investment scaling across the entire technology stack. The 55 companies that raised $100 million or more represent the vanguard of American innovation in artificial intelligence, tackling challenges from silicon to software. While the number of individual $1 billion+ rounds decreased, the total capital deployed and the number of companies receiving repeated mega-funding increased, signaling a maturation of the market. Investors are not just betting on a single winner but are building a portfolio across infrastructure, applications, and foundational research. As early 2026 deals like xAI’s $20 billion round suggest, this momentum shows no sign of abating. The collective success of these 55 AI startups in 2025 sets a formidable foundation for the next phase of technological transformation, with profound implications for the global economy and society.
FAQs
Q1: How many AI startups raised over $100 million in the US in 2025?
According to the data, 55 U.S.-based artificial intelligence startups secured venture funding rounds of $100 million or more during the 2025 calendar year.
Q2: Which AI startup raised the most money in 2025?
OpenAI raised the largest single round, a $40 billion investment in March that valued the company at $300 billion. Anthropic also raised a monumental $13 billion round in September.
Q3: Did funding increase or decrease from 2024 to 2025?
The number of companies securing mega-rounds increased from 49 to 55. However, 2025 saw fewer individual rounds exceeding $1 billion compared to 2024. The trend shifted toward more companies raising multiple large rounds within the year.
Q4: What sectors received the most AI investment in 2025?
Major investment flowed into AI infrastructure/hardware, healthcare AI, enterprise/developer tools, generative media platforms, and fundamental AI research labs.
Q5: Who were the most active investors in AI startups during 2025?
Leading venture firms like Andreessen Horowitz, Lightspeed, and Sequoia were highly active. Strategic corporate investors, particularly Nvidia, AMD, and large cloud providers, also participated heavily in many rounds.