Updated July 2026. By Remy Beaumont.
Total raised in the US this week: $1.5bn across 26 disclosed rounds.
Key takeaways
US funding rounds this week totalled roughly $1.5bn across 26 disclosed deals, a mid-sized week after the Atoms-dominated $1.7bn single round seven days earlier.
The headline deal was Antares' $470m Series C for nuclear microreactors, announced on the wire and aimed squarely at defence trade press rather than mainstream tech media.
The biggest surprise was Simile raising $200m at a $2bn valuation just five months after its $100m Series A, for a product that surveys simulated people instead of real ones.
AI led on deal count with roughly 50% of all rounds, but energy and climate narrowly led on dollars at about $525m, entirely on the back of Antares.
What did the US funding week look like?
The week ending 31st July delivered roughly $1.5bn across 26 disclosed US rounds, a solid mid-table week. Thirteen of those 26 deals, about 50%, were AI software, infrastructure or robotics rounds worth a combined $500m or so, yet a single nuclear energy deal meant AI did not top the dollar table.
The texture of the week matters more than the total. Three of the top five rounds were momentum raises announced within months of a prior round, and two of the biggest announcements bypassed mainstream tech press entirely in favour of trade and finance media. If you are planning a raise announcement, this week is a masterclass in choosing your channel deliberately. We track the monthly picture in our biggest US funding rounds this month roundup.
Which was the biggest round this week?
Antares, the Torrance, California nuclear microreactor company, raised a $470m Series C co-led by Paradigm and Caffeinated Capital, with Point72 Ventures, Shine Capital and Industrious Ventures participating. The round splits into $370m of equity and $100m of debt, and funds factory-built microreactors to power US military bases off-grid from 2028. Sources: Business Wire, Tech Funding News.
The announcement teardown is where this gets interesting. Antares went wire-first, not exclusive-first: a Business Wire release at roughly 11:30 ET on Monday 27th July, with no outlet breaking it early. The pickup skewed heavily to defence and government contracting media, Washington Technology, GovConWire and Tectonic Defense, while TechCrunch never covered it at all. That is not a failure, it is targeting: the buyers, partners and policy audience Antares needs read trade press, not tech blogs.
Two more PR choices stand out. First, the release anchored the raise to hard external deadlines: the Mark-0 reactor reaching criticality at Idaho National Laboratory in June, and Executive Order 14299's requirement for an advanced reactor on a military base by September 2028. Urgency was borrowed from Washington rather than manufactured. Second, Antares disclosed the debt and equity split, which is rare in megaround PR and reads as institutional confidence.
The other big rounds this week
Simile, $200m Series B at $2bn valuation. Greenoaks led, with Index Ventures, Bain Capital Ventures and CVS Health Ventures. Simile builds synthetic users, AI simulations of human behaviour that let CVS and Gallup test decisions before launch. Announced via a TechCrunch story leaning hard on the five-months-after-Series-A momentum angle.
ThreatLocker, $190m Series F. Elephant led, with D. E. Shaw Ventures and Koch Disruptive Technologies. The Orlando Zero Trust security firm protects over 70,000 organisations and is extending into AI-agent controls. Announced by wire release.
CAIS, $170m Series D at a $2bn-plus valuation. Vista Equity Partners led. The New York alternative-investments marketplace chose a Citywire exclusive, placing the story with the outlet its adviser audience actually reads. Same channel logic as Antares, different vertical.
Enigma, $71m seed. Index Ventures and Ribbit Capital co-led, with angels from OpenAI, Anthropic, DeepMind and xAI. The robot-control startup landed a TechCrunch story built on a single vivid promise: making a robot as easy to control as adjusting the volume.
Fish Audio, $52m seed. Coreline Ventures and Capital Today led. The Palo Alto voice-AI startup announced with traction as the story: $21m ARR and 8m users in year one, per TechCrunch.
Where is US capital flowing?
By dollars, energy and climate led US funding rounds this week at roughly $525m across just two deals, Antares plus Claros Technologies' $55m Series B for PFAS destruction. AI followed at about $500m across 13 deals, fintech at roughly $202m across three, cybersecurity at $190m from ThreatLocker alone, and health at about $65m across five.
The honest read: if you class Antares as defence, which its PR strategy clearly does, defence-adjacent capital was the runaway winner. Founders in dual-use sectors should note how much of this week's money followed government demand signals rather than consumer ones. For European founders eyeing this market, our playbook on how European startups win US press covers the channel choices on display this week.
Notable US launches this week
Pangram 4 and Pangram Image. Pangram Labs launched a next-generation AI-text detector claiming over 99% accuracy, plus its first AI-image detector, paired with a $9m Menlo Ventures raise. A textbook launch-plus-funding double announcement. Source: Business Wire.
Pilot Protocol. Emerged from stealth claiming an internet for AI agents already carrying roughly 250,000 agents and 2bn requests per day, with a $4.5m raise attached. Stealth exits with live traction numbers land far harder than roadmap promises. Source: TechStartups.
What should founders raising soon do this week?
Pick the press your buyers read, not the press you read. Antares skipped TechCrunch for defence trade media; CAIS chose a Citywire exclusive for advisers. Both landed with the audience that moves revenue.
Anchor your announcement to an external deadline or milestone. Antares borrowed urgency from an executive order and a national lab milestone. Find the regulatory clock or industry moment your raise plugs into.
Lead with traction numbers, not vision. Fish Audio's $21m ARR and Pilot Protocol's 2bn daily requests did the persuading. If you have a number, put it in the first sentence.
Momentum is a story in itself. Simile's five-months-later round was the week's most covered deal partly because velocity is the hook. If you re-raise quickly, make the gap the headline.
The rest of the week's top rounds
Freehand, $75m Series B, Battery Ventures and NewRoad co-led, AI supply-chain agents (TechStartups)
Claros Technologies, $55m Series B, PFAS destruction (PRNewswire)
Encore AI, $30m Series A, AI agents trained on customer calls (TechCrunch)
Flourish Health, $26m Series A, in-home youth mental healthcare (TechStartups)
Istari Digital, $22.6m, defence digital engineering (TechStartups)
Array Labs, $21m strategic, radar satellite constellations (TechStartups)
InvestiFi, $20m, led by Vibe Credit Union; Henry AI, $16.5m Series A, FirstMark; Centralize, $15m Series A, NEA and Salesforce Ventures; Pangram, $9m, Menlo Ventures (AlleyWatch, SiliconANGLE)
FAQ
How much did US startups raise this week? Roughly $1.5bn across 26 disclosed rounds in the week ending 31st July 2026, based on rounds reported by Crunchbase News, TechCrunch, TechStartups and AlleyWatch. Friday announcements may push the final figure higher.
What was the biggest US funding round this week? Antares' $470m Series C, co-led by Paradigm and Caffeinated Capital, to deploy nuclear microreactors on US military bases from 2028.
Which sector led US funding rounds this week? AI led on volume with about 50% of deals; energy and climate led on dollars at roughly $525m thanks to Antares.
Was this a strong week for US venture funding? Mid-sized. It trailed the prior week's headline total, which was inflated by Atoms' single $1.7bn round, but deal breadth across 26 disclosed rounds was healthy.
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