As of December 2025 Alliant Energy has a market cap of โน1.500 Trillion. This makes Alliant Energy the world's 1299th most valuable company by market cap according to our data. The market capitalization, commonly called market cap, is the total market value of a publicly traded company's outstanding shares and is commonly used to measure how much a company is worth.
On Dec 23rd, 2025 the market cap of Alliant Energy was reported to be: