Houston Startups Raise Nearly $1 Billion in First Half of 2026

Houston startups pulled in nearly $1 billion in venture capital during the first half of 2026, according to Pitchbook data. InnovationMap and its sister site EnergyCapitalHTX.com tracked 17 Houston companies that closed funding rounds between January and June.

The two largest deals alone account for most of the haul: a $1 billion equity investment in VoltaGrid and a $525 million round at Axiom Space.

Which deals topped the list?

VoltaGrid secured the half-year's largest commitment in May: a $1 billion strategic equity investment from Blackstone and Houston-based Halliburton. The deal split into a $775 million primary capital raise and a $225 million secondary purchase from existing investors. Founded in 2020, VoltaGrid supplies behind-the-meter mobile power generation for data centers, microgrids and industrial customers.

Axiom Space closed an oversubscribed round at more than $525 million in June. The company added $175 million to the $350 million it announced in February, a raise led by Type One Ventures and Qatar Investment Authority. Japan's MUFG Bank joined as a new investor in June. Axiom will direct the proceeds toward its commercial space station and production of the AxEMU spacesuit under its NASA contract.

Cart.com raised $180 million in growth capital from private equity firm Springcoast Partners in March, pushing the commerce and logistics platform past $1 billion in total funding since its 2020 founding. The company plans to scale its logistics network, expand AI capabilities and develop workflow automation tools.

What did the energy and climatetech rounds deliver?

Energy transition companies dominated the mid-size deals.

• Utility Global raised $100 million in an ongoing Series D led by Ara Partners and APG Asset, reported in February, to deploy its H2Gen hydrogen technology, which produces clean hydrogen from water and industrial off-gases without electricity.
• Sage Geosystems closed a $97 million Series B in January, co-led by Ormat Technologies and Carbon Direct Capital, to build its first commercial pressure-geothermal power facility at an existing Ormat plant.
• NanoTech Materials closed a $29.4 million Series A in April, led by Austin-based HPI Real Estate & Investments, to scale its patented Insulative Ceramic Particle technology.
• Ace Green Recycling secured $32 million in PIPE financing with Athena Technology Acquisition Corp. II in May, ahead of a merger that would list the battery recycler on Nasdaq under ticker "AGXI."
• Helix Earth Technologies closed a $12 million Seed 2 round in April, led by Houston's Veriten, to scale manufacturing of retrofit dehumidification systems for commercial HVAC.
• Artemis (formerly Monalee) raised $6 million from 10 investors in March, co-led by Long Journey and Copec WIND Ventures, for its AI platform serving solar and battery storage contractors.
• DexMat closed a $5 million seed round in February, led by non sibi ventures, plus $3 million in non-dilutive funding, to scale Galvorn, its Rice University-developed carbon nanotube copper alternative.
• Aquanta Vision secured pre-seed funding in May with participation from EIC Rose Rock, joining backers such as Marathon Petroleum and Chevron Technology Ventures, to commercialize methane leak detection software.

Who raised in health, fintech and deep tech?

Casimir emerged from stealth in May with a $12 million oversubscribed seed round led by Austin-based Scout Ventures, exceeding its original $8 million target. Tim Draper participated. The company's semiconductor chips generate power from quantum vacuum fields without batteries or charging, and Casimir plans to commercialize its first-generation MicroSparc chip by 2028.

Coya Therapeutics (NASDAQ: COYA) raised $11.1 million in a February private placement. Dr. Reddy's Laboratories invested $10 million; Greenlight Capital contributed $1.1 million. Proceeds will scale manufacturing of low-dose IL-2, a component of COYA 302, its therapy targeting ALS and other neurodegenerative diseases.

Wellysis, a Seoul-based wearable biosensing company with its U.S. subsidiary in Houston, closed a $13.5 million pre-IPO round in February led by Korea Investment Partners, Kyobo Life Insurance, Kyobo Securities, Kolon Investment and a fund backed by SBI Investment and Samsung Securities. The round brings total capital to about $30 million. The company targets a KOSDAQ listing in Q4 2026 or Q1 2027.

Smaller rounds rounded out the half. Receipts Depositary Corporation closed a $7 million oversubscribed round in June led by LiveOak Ventures to scale its depositary receipt platform for digital and alternative assets. TrueLeap Inc. raised an oversubscribed $3.3 million seed in January, led by Joe Swinbank Family Limited Partnership, to deploy what the company calls its "edge AI, integrated learning systems and last-mile broadband across underserved communities." Paige, the life planning software firm founded by CEO Emily Cisek in 2020 as The Postage, took a $2.5 million investment from Alabama-based 22nd State Banking Company to expand its AI-driven tools.

With VC funding in Houston already up nearly 50% in Q1 2026 alone, according to InnovationMap's reporting, the second half of the year will test whether the momentum — driven heavily by energy transition and power infrastructure demand — can hold.