US Startups Raised $20.83B in October, Up 71% Year Over Year

US startups raised $20.83B across 563 rounds in October 2026, down 25% from September but up 71% from October 2025, according to AlleyWatch's US startup funding data. Four rounds of $1B or more — Ramp, Tenstorrent, Flapping Airplanes and Kalshi — totaled $5.35B, or 26% of the month's capital. The surprise sat at Series A: the stage pulled $5.11B, up 72% from September's $2.97B.

By Daniel Okafor

Where did the money concentrate?

Concentration was the month's defining trait. The 43 rounds of $100M or more raised $14.25B, or 68% of all October capital. The top 10 rounds alone totaled $8.77B, a 42% share. That leaves 553 rounds to split the remainder.

The four $1B+ deals break down as follows:

• Ramp, spend management: $1.85B Series G led by Dragoneer and Thrive Capital, with Founders Fund participating
• Tenstorrent, AI chips: $1.5B Series E led by Trace Capital and Innovation X, at a $6.2B valuation
• Flapping Airplanes, an AI research lab: $1B Series A from Index Ventures and Lux Capital, at a $6B valuation
• Kalshi, prediction markets: $1B Series G co-led by Sequoia Capital and Wellington Management

What happened to Series A?

Three outsized rounds inflated the stage. Flapping Airplanes ($1B), TypeSafe AI ($870M) and Atlas Atomics ($400M) took $2.27B, or 44% of Series A capital. TypeSafe AI, which builds AI models and tools, raised its round at a $7.5B valuation with Andreessen Horowitz leading. Atlas Atomics raised about $400M for a nuclear reactor at a $1.9B valuation.

Behind them came Warp Sciences ($215M), Arda ($160M) and Eka Robotics ($150M). The stage ran 121 rounds in total, or 24.5% of the month's capital.

Did late-stage really cool?

It did, by share and by dollars. Series C and later raised $10.77B across 51 rounds, 52% of the month. In September the same stage raised $19.84B, or 71% of that month's total. Late-stage still produced the single biggest check: Ramp's $1.85B.

Other late-stage deals included Modal Labs, an AI cloud infrastructure company, which raised a $750M Series D led by Accel. Bedrock Robotics raised a $600M Series C co-led by CapitalG and Emergence Capital for autonomous construction equipment. ASI, which builds AI for aviation and defense, raised $325M led by Spark Capital. Xona followed with a $250M Series D.

How did the other stages perform?

Series B ran 50 rounds for $2.98B, or 14.3% of capital. Oratomic led with $475M from ARCH Venture Partners for fault-tolerant quantum computers — a round closed just three months after its Series A. Armadin ($255.5M), Vinci ($250M), Arena ($200M) and Type One Energy ($200M) followed.

Early-stage ran 341 rounds for $1.98B, the smallest stage share at 9.5%. Dream Labs topped the group with a $90M seed led by B Capital for a robot foundation model. Oro Mobility and OptimizeGEO.ai raised $80M each, then &Truth ($70M), Hone ($60M) and Teddy AI ($60M). The median early-stage round was $2.7M — a useful check against the headline numbers, since the typical deal stayed small.

Which sectors drew the biggest checks?

AI infrastructure set the pace. Companies tagged as AI raised about $13.76B, roughly two-thirds of the month, led by Tenstorrent, Flapping Airplanes, TypeSafe AI and Modal. Those four firms are building chips, models and cloud capacity.

The rest of the map spread wide:

• Fintech: Ramp and Kalshi raised $2.85B between them
• Hard tech: Bedrock Robotics, Oratomic and Atlas Atomics each raised $400M or more
• Defense and space: ASI ($325M), Xona ($250M), Firehawk Aerospace ($150M)
• Health: Pathos ($237M), Warp Sciences ($215M), Star Therapeutics ($200M)
• Cybersecurity: Armadin led with $255.5M

Why does New York stand out?

New York companies raised $4.94B across 54 rounds, or 23.7% of US capital, on just 9.6% of rounds. The average NYC round was $91.6M against a national average of $37.0M. Ramp, Kalshi and Modal alone raised $3.60B, and NYC took 39.6% of US late-stage dollars. The city's capital total rose 61% from September while the national figure fell 25%, and it rose 254% year over year.

What comes next for Q4?

Q3 closed at about $65.43B, and Q4 opens with $20.83B. The month leaned on four $1B+ rounds and a Series A stage swollen by three outsized raises, so November will show whether capital keeps flowing to a handful of companies or spreads across more deals. AlleyWatch notes that October figures will move as late-reported rounds arrive. The methodology counts disclosed round sizes only, excludes corporate rounds, private equity and debt, and puts Pre-Seed, Seed, Angel, Accelerator and Incubator rounds in the early-stage bucket.