Alliant Energy Corp SEC filings LNT
Alliant Energy Corp has 1,000 filings in SEC EDGAR's recent list, going back to Jan 31, 2014. Its latest annual report, Form ARS, was filed on Mar 31, 2026 for the period ended Dec 31, 2025. The latest quarterly report (Form 10-Q) was filed on Oct 30, 2026, covering the quarter ended Sep 30, 2026. The most recent current report (Form 8-K) was filed on Oct 30, 2026 (results of operations). The company's fiscal year ends on December 31.
| Form | Description | Filed | Period |
|---|---|---|---|
| 11-K | Employee savings plan report | Jun 16, 2026 | Dec 31, 2025 |
| POSASR | Filing | Sep 22, 2025 | — |
| 11-K | Employee savings plan report | Jun 24, 2025 | Dec 31, 2024 |
| PX14A6G | Filing | May 8, 2025 | — |
| 11-K | Employee savings plan report | Jun 20, 2024 | Dec 31, 2023 |
| UPLOAD | Letter from the SEC | Dec 19, 2023 | — |
| CORRESP | Letter to the SEC | Dec 15, 2023 | — |
| CORRESP | Letter to the SEC | Dec 1, 2023 | — |
| UPLOAD | Letter from the SEC | Nov 28, 2023 | — |
| 11-K | Employee savings plan report | Jun 22, 2023 | Dec 31, 2022 |
| 11-K | Employee savings plan report | Jun 17, 2022 | Dec 31, 2021 |
| 11-K | Employee savings plan report | Jun 17, 2021 | Dec 31, 2020 |
| 11-K | Employee savings plan report | Jun 18, 2020 | Dec 31, 2019 |
| 11-K | Employee savings plan report | Jun 20, 2019 | Dec 31, 2018 |
| CERT | Filing | Dec 31, 2018 | — |
| 8-A12B | Filing | Dec 28, 2018 | — |
| 25 | Filing | Dec 28, 2018 | — |
| 11-K | Employee savings plan report | Jun 27, 2018 | Dec 31, 2017 |
| UPLOAD | Letter from the SEC | Aug 24, 2017 | — |
| CORRESP | Letter to the SEC | Aug 21, 2017 | — |
| UPLOAD | Letter from the SEC | Aug 10, 2017 | — |
| 11-K | Employee savings plan report | Jun 16, 2017 | Dec 31, 2016 |
| UPLOAD | Letter from the SEC | Aug 9, 2016 | — |
| CORRESP | Letter to the SEC | Jul 29, 2016 | — |
| UPLOAD | Letter from the SEC | Jul 18, 2016 | — |
| 11-K | Employee savings plan report | Jun 27, 2016 | Dec 31, 2015 |
| 11-K | Employee savings plan report | Jun 24, 2015 | Dec 31, 2014 |
| NO ACT | Auto-generated paper document | Jan 6, 2015 | Jan 6, 2015 |
| 11-K | Employee savings plan report | Jun 20, 2014 | Dec 31, 2013 |
Showing 29 filings. Main filings leave out insider and ownership forms such as Form 4; choose a type above to see them. Each form opens on SEC.gov. Older filings are on SEC EDGAR.
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Company profile
- Industry
- Electric & Other Services Combined (SIC 4931)
- Listed as
- LNT (Nasdaq)
- Fiscal year ends
- December 31
- Incorporated in
- WI
- Headquarters
- Madison, WI
- SEC filer status
- Large accelerated filer
- SEC CIK
- 352541
- Former names
- ALLIANT ENERGY CORP (until Oct 30, 2026); INTERSTATE ENERGY CORP (until May 13, 1999); WPL HOLDINGS INC (until Feb 23, 1998)
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Source: SEC EDGAR filings. This is company-reported data, not investment advice.