Alliant Energy
Alliant Energy Corporation (NASDAQ: LNT) operates as a regulated investor-owned public utility holding company headquartered in Madison, Wisconsin, with its primary business conducted through two wholly-owned public utility subsidiaries: Interstate Power and Light Company and Wisconsin Power and Light Company. The… From the company’s description.
Margins and return on equity change in ; everything else in percent. Fewer shares and less debt are shown plainly, not as bad news — it depends what you make of buybacks. Dotted labels explain each measure. is shown separately from the annual figures.
What Alliant Energy does
In the company’s own words
Alliant Energy Corporation (NASDAQ: LNT) operates as a regulated investor-owned public utility holding company headquartered in Madison, Wisconsin, with its primary business conducted through two wholly-owned public utility subsidiaries: Interstate Power and Light Company and Wisconsin Power and Light Company. The company maintains its corporate website at www.alliantenergy.com.
Alliant Energy's core business focuses on providing regulated electric and natural gas utility services to approximately 1.01 million electric customers and approximately 435,000 natural gas customers across the Midwest. Interstate Power and Light Company serves approximately 505,000 electric and 230,000 natural gas retail customers in Iowa, while also selling electricity to wholesale customers in Illinois and Iowa. Wisconsin Power and Light Company serves approximately 505,000 electric and 205,000 natural gas retail customers in Wisconsin, with wholesale electricity sales to customers in Wisconsin.
The company operates as a vertically integrated utility, engaged in the generation, transmission, and distribution of electricity and the distribution and transportation of natural gas. Alliant Energy's customer base spans diverse industries including farming, agriculture, industrial manufacturing, chemical production including ethanol, pipeline transportation, packaging, food processing, and data centers.
Beyond its core utility operations, Alliant Energy maintains non-utility holdings organized under Alliant Energy Finance, LLC, which manages a portfolio of subsidiaries and investments. These include a 16 percent ownership interest in American Transmission Company, a transmission-only company, a 50 percent cash equity ownership interest in a 225 megawatt non-utility wind farm in Oklahoma, and Travero, a supply chain solutions company providing short-line rail freight service, Mississippi River barge and rail terminal operations, and freight brokerage services.
As of December 31, 2025, Alliant Energy employed approximately 2,948 full- and part-time employees across its operations, with 58 percent covered by collective bargaining agreements. The company is subject to comprehensive regulation by the Federal Energy Regulatory Commission, the Iowa Utilities Commission, and the Public Service Commission of Wisconsin, governing retail utility rates, service standards, environmental compliance, and capital investments.
Company details
- Sector
- Utilities
- Industry (SIC)
- Electric, Gas & Water
- Headquarters
- MADISON, WI
- Fiscal year end
- December
- CIK
- 352541
- SIC
- 4931
Financial performance, year by year
Fiscal 2013–2025 · USDThe full income statement, balance sheet and cash flow for each of these years — every figure traceable to its filing — is on the Financials tab with a free account.
Who owns Alliant Energy — and what changed
Funds as of 2026Q2 · superinvestors as of 2026-06-30
Largest fund holders · Alliant Energy’s weight in each
Fund ownership is a floor, not a census — pensions, insurers and people holding shares directly are not visible here.
Alliant Energy’s bonds, as funds hold them
Funds report holding 28 issues of Alliant Energy’s debt, $1.27B at market value — what funds hold, not the company’s total debt. Weighted-average coupon 4.50%, maturing 2027 to 2056.
Fund ownership counts N-PORT filers only, so it is a floor rather than a census — pensions, insurers and direct holders are not visible here, and the remainder is not “held by individuals”.
Every fund and institutional holder, quarter by quarter, is on the Ownership tab with a free account.
Recent filings
All filings →Each filing opens into its own statements and disclosures here.
Put this business in context.
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