Helion Energy — Startup Profile

Commercial fusion power using field-reversed configuration technology

HQ: Everett, WA, United States | Founded: 2013 | Employees: 500-1,000 | Stage: Late Stage (Series G) | Website: https://helionenergy.com

About

Helion Energy is developing commercial fusion power using field-reversed configuration technology. The company aims to build the world's first fusion power plant and has signed the first-ever fusion power purchase agreement with Microsoft.

The Take

Helion Energy is racing to build the world's first commercial fusion power plant, with a signed power purchase agreement with Microsoft targeting 2028 delivery. The company's Polaris prototype has achieved record-breaking plasma temperatures and is the first privately funded fusion machine to use deuterium-tritium fuel. With Sam Altman as a major investor and a $15.5B valuation, Helion is the most well-funded fusion startup and the closest to commercial reality.

Key Metrics

• Total Funding: $1.5B
• Last Round: Series G ($465M)
• Founded: 2013
• Headcount: 500-1,000
• Valuation: $15.5B

Funding Rounds

• Round: $465M (2026-06-04) — Thrive Capital
• Round: $425M (2025-01-28) — Sam Altman

Key People

• David Kirtley
• Chris Pihl

Key Competitors

• Commonwealth Fusion Systems —
• TAE Technologies —

Timeline Highlights

• 2026-06-04: Series G
• 2025-01-28: Series F
• 2013-01-01: Founded

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