Helion funding round grows to $500M amid Microsoft timeline uncertainty

Fusion startup Helion Energy increased its Series G round from $465 million to $500 million, attracting new investors. The company committed to deliver 50 MW of power to a Microsoft data center in Washington by 2028, but full capacity may slip to 2030.

• Round grew by $35 million to $500 million, total raised over $1.5 billion
• Company headcount exceeded 800 employees, opened office in downtown Seattle
• 50 MW Orion facility was laid down in July 2025
• Full capacity may only be reached by 2030