Helion raises $465M Series G at $15.5B valuation

Helion Energy raised $465 million in a Series G round led by Thrive Capital, with the company valued at $15.5 billion in the transaction. The financing brings Helion’s total capital raised to about $1.5 billion and is intended to speed commercial deployment of its fusion technology, expand manufacturing, and support delivery of clean electricity to customers.

The round included new backers such as Lux Capital, Bill Ford, Alta Park Capital, Anti Fund, BoxGroup, and Peak XV Partners, alongside returning investors including Lightspeed Venture Partners, Mithril Capital, Good Ventures Foundation, SoftBank Vision Fund 2, Capricorn Technology Impact Funds, and a university endowment fund. Helion, based in Everett, Washington, is building commercial fusion power systems and has positioned the new capital around its first power plant and broader scale-up plans.

The financing underscores continued investor appetite for fusion as a long-horizon energy technology, especially as demand for reliable power grows. Helion’s latest raise also nearly triples its valuation from its prior funding round in early 2025, reflecting sharper market confidence in the company’s path toward commercial deployment.