Alliant Energy maintains its principal executive offices in Madison, Wisconsin. Alliant Energy operates as a regulated investor-owned public utility holding company, and its purpose-driven strategy is to serve its customers and build stronger communities. Alliant Energy’s primary focus is to provide regulated electric and natural gas service to approximately 1,010,000 electric and approximately 435,000 natural gas customers in the Midwest through its two public utility subsidiaries, IPL and WPL. The primary first tier wholly-owned subsidiaries of Alliant Energy are as follows: 1) IPL - is a public utility engaged principally in the generation and distribution of electricity and the distribution and transportation of natural gas to retail customers in select markets in Iowa. IPL provides utility services to incorporated communities as directed by the IUC and utilizes non-exclusive franchises, which cover the use of public right-of-ways for utility facilities in incorporated communities for a maximum term of 25 years. At December 31, 2025, IPL supplied electric and natural gas service to approximately 505,000 and 230,000 retail customers, respectively, in Iowa.