Accessibility Menu

The Largest Utilities Companies by Market Cap in December 2025

NextEra Energy, Iberdrola, and Constellation Energy lead the utilities sector.

By Lyle DalyUpdated Dec 4, 2025 at 10:02 PM | Fact-checked by Frank Bass
Follow

Key Points

  • NextEra Energy leads as the most valuable utility company with a market cap of $177 billion.
  • Iberdrola focuses on renewable energy, producing a record 83,300 GWh in clean energy in 2024.
  • Constellation Energy became the largest U.S. clean energy provider after acquiring Calpine Corp. in 2025.
Advertisement

Premium Investing Services

Invest better with The Motley Fool. Get stock recommendations, portfolio guidance, and more from The Motley Fool's premium services.