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 |
|---|---|---|---|
| 10-Q | Quarterly report | Oct 30, 2026 | Sep 30, 2026 |
| 8-K |
Current report
Results of operations
|
Oct 30, 2026 | Oct 29, 2026 |
| 8-K |
Current report
Material agreement, New debt
|
Oct 28, 2026 | Oct 26, 2026 |
| 8-K |
Current report
Other events
|
Aug 21, 2026 | Aug 21, 2026 |
| 10-Q | Quarterly report | Jul 31, 2026 | Jun 30, 2026 |
| 8-K |
Current report
Results of operations
|
Jul 31, 2026 | Jul 30, 2026 |
| 11-K | Employee savings plan report | Jun 16, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Shareholder vote results
|
May 21, 2026 | May 20, 2026 |
| 10-Q | Quarterly report | May 1, 2026 | Mar 31, 2026 |
| 8-K |
Current report
Results of operations
|
May 1, 2026 | Apr 30, 2026 |
| ARS | Annual report to shareholders | Mar 31, 2026 | Dec 31, 2025 |
| DEFA14A | Additional proxy material | Mar 31, 2026 | — |
| DEF 14A | Proxy statement | Mar 31, 2026 | May 20, 2026 |
| 8-K |
Current report
Material agreement
|
Mar 19, 2026 | Mar 19, 2026 |
| 424B5 | Prospectus supplement | Mar 19, 2026 | — |
| 8-K |
Current report
Material agreement, New debt
|
Mar 4, 2026 | Mar 2, 2026 |
| 10-K | Annual report | Feb 20, 2026 | Dec 31, 2025 |
| 8-K |
Current report
Results of operations
|
Feb 20, 2026 | Feb 19, 2026 |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| S-8 POS | Filing | Feb 9, 2026 | — |
| 8-K |
Current report
Officer or director change
|
Jan 8, 2026 | Jan 5, 2026 |
| 8-K |
Current report
Officer or director change
|
Dec 16, 2025 | Dec 10, 2025 |
| 8-K |
Current report
Other events
|
Dec 5, 2025 | Dec 2, 2025 |
| 10-Q | Quarterly report | Nov 7, 2025 | Sep 30, 2025 |
| 8-K |
Current report
Results of operations
|
Nov 7, 2025 | Nov 6, 2025 |
| 8-K |
Current report
Other events
|
Sep 26, 2025 | Sep 23, 2025 |
| 424B5 | Prospectus supplement | Sep 25, 2025 | — |
| FWP | Free writing prospectus | Sep 23, 2025 | — |
| 424B5 | Prospectus supplement | Sep 23, 2025 | — |
| POSASR | Filing | Sep 22, 2025 | — |
| 8-K |
Current report
Other events
|
Sep 11, 2025 | Sep 8, 2025 |
| 10-Q | Quarterly report | Aug 8, 2025 | Jun 30, 2025 |
| 8-K |
Current report
Results of operations
|
Aug 8, 2025 | Aug 7, 2025 |
| 11-K | Employee savings plan report | Jun 24, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Shareholder vote results
|
May 20, 2025 | May 16, 2025 |
| 8-K |
Current report
Other events
|
May 19, 2025 | May 13, 2025 |
| 8-K |
Current report
Material agreement, New debt, Unregistered share sale, Other events
|
May 15, 2025 | May 12, 2025 |
| 8-K |
Current report
Material agreement
|
May 9, 2025 | May 9, 2025 |
| 424B5 | Prospectus supplement | May 9, 2025 | — |
| 10-Q | Quarterly report | May 9, 2025 | Mar 31, 2025 |
| 8-K |
Current report
Results of operations
|
May 9, 2025 | May 8, 2025 |
| PX14A6G | Filing | May 8, 2025 | — |
| ARS | Annual report to shareholders | Apr 1, 2025 | Dec 31, 2024 |
| DEFA14A | Additional proxy material | Apr 1, 2025 | — |
| DEF 14A | Proxy statement | Apr 1, 2025 | May 16, 2025 |
| 8-K |
Current report
Officer or director change
|
Mar 10, 2025 | Mar 7, 2025 |
| 8-K |
Current report
Material agreement, New debt
|
Mar 3, 2025 | Mar 3, 2025 |
| 10-K | Annual report | Feb 21, 2025 | Dec 31, 2024 |
| 8-K |
Current report
Results of operations
|
Feb 21, 2025 | Feb 20, 2025 |
| 8-K |
Current report
Officer or director change
|
Feb 11, 2025 | Feb 7, 2025 |
| 8-K |
Current report
New debt
|
Dec 18, 2024 | Dec 18, 2024 |
| 10-Q | Quarterly report | Nov 1, 2024 | Sep 30, 2024 |
| 8-K |
Current report
Results of operations
|
Nov 1, 2024 | Oct 31, 2024 |
| 8-K |
Current report
Other events
|
Sep 6, 2024 | Sep 4, 2024 |
| 10-Q | Quarterly report | Aug 2, 2024 | Jun 30, 2024 |
| 8-K |
Current report
Results of operations
|
Aug 2, 2024 | Aug 1, 2024 |
| 8-K | Current report | Jul 26, 2024 | Jul 22, 2024 |
| 8-K |
Current report
Officer or director change
|
Jul 15, 2024 | Jul 10, 2024 |
| 8-K |
Current report
Impairment
|
Jun 24, 2024 | Jun 20, 2024 |
| 11-K | Employee savings plan report | Jun 20, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Material agreement, New debt, Other events
|
Jun 6, 2024 | Jun 3, 2024 |
| 8-K |
Current report
Shareholder vote results
|
May 20, 2024 | May 17, 2024 |
| 10-Q | Quarterly report | May 3, 2024 | Mar 31, 2024 |
| 8-K |
Current report
Results of operations
|
May 3, 2024 | May 2, 2024 |
| ARS | Annual report to shareholders | Apr 2, 2024 | Dec 31, 2023 |
| DEFA14A | Additional proxy material | Apr 2, 2024 | — |
| DEF 14A | Proxy statement | Apr 2, 2024 | May 17, 2024 |
| 8-K |
Current report
Officer or director change
|
Mar 8, 2024 | Mar 7, 2024 |
| 8-K |
Current report
Other events
|
Mar 7, 2024 | Mar 4, 2024 |
| 8-K |
Current report
Material agreement, New debt
|
Mar 5, 2024 | Mar 1, 2024 |
| 10-K | Annual report | Feb 16, 2024 | Dec 31, 2023 |
| 8-K |
Current report
Results of operations
|
Feb 16, 2024 | Feb 15, 2024 |
| 8-K |
Current report
Officer or director change
|
Feb 13, 2024 | Feb 8, 2024 |
| UPLOAD | Letter from the SEC | Dec 19, 2023 | — |
| CORRESP | Letter to the SEC | Dec 15, 2023 | — |
| S-3ASR | Automatic shelf registration | Dec 15, 2023 | — |
| CORRESP | Letter to the SEC | Dec 1, 2023 | — |
| UPLOAD | Letter from the SEC | Nov 28, 2023 | — |
| 8-K |
Current report
Material agreement, New debt, Other events
|
Nov 13, 2023 | Nov 7, 2023 |
| S-3ASR | Automatic shelf registration | Nov 6, 2023 | — |
| 10-Q | Quarterly report | Nov 3, 2023 | Sep 30, 2023 |
| 8-K |
Current report
Results of operations
|
Nov 3, 2023 | Nov 2, 2023 |
| 8-K |
Current report
Officer or director change
|
Oct 26, 2023 | Oct 25, 2023 |
| 8-K |
Current report
Other events
|
Sep 21, 2023 | Sep 18, 2023 |
| 10-Q | Quarterly report | Aug 4, 2023 | Jun 30, 2023 |
| 8-K |
Current report
Results of operations
|
Aug 4, 2023 | Aug 3, 2023 |
| 8-K |
Current report
Officer or director change
|
Jul 14, 2023 | Jul 11, 2023 |
| 11-K | Employee savings plan report | Jun 22, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Shareholder vote results
|
May 25, 2023 | May 23, 2023 |
| 10-Q | Quarterly report | May 5, 2023 | Mar 31, 2023 |
| 8-K |
Current report
Results of operations
|
May 5, 2023 | May 4, 2023 |
| ARS | Annual report to shareholders | Apr 4, 2023 | Dec 31, 2022 |
| DEFA14A | Additional proxy material | Apr 4, 2023 | — |
| DEF 14A | Proxy statement | Apr 4, 2023 | — |
| 8-K |
Current report
Other events
|
Mar 30, 2023 | Mar 27, 2023 |
| 8-K |
Current report
New debt
|
Mar 16, 2023 | Mar 15, 2023 |
| 8-K |
Current report
New debt, Unregistered share sale
|
Mar 13, 2023 | Mar 10, 2023 |
| 8-K |
Current report
Material agreement, New debt, Unregistered share sale, Other events
|
Mar 3, 2023 | Feb 27, 2023 |
| 10-K | Annual report | Feb 24, 2023 | Dec 31, 2022 |
| 8-K |
Current report
Results of operations
|
Feb 24, 2023 | Feb 23, 2023 |
| 8-K |
Current report
Officer or director change
|
Jan 13, 2023 | Jan 13, 2023 |
| 8-K |
Current report
Officer or director change
|
Jan 4, 2023 | Jan 4, 2023 |
| 8-K |
Current report
Material agreement
|
Dec 15, 2022 | Dec 14, 2022 |
| 424B5 | Prospectus supplement | Dec 15, 2022 | — |
| 10-Q | Quarterly report | Nov 8, 2022 | Sep 30, 2022 |
| 8-K |
Current report
Results of operations
|
Nov 8, 2022 | Nov 7, 2022 |
| 8-K |
Current report
Other events
|
Aug 15, 2022 | Aug 8, 2022 |
| 10-Q | Quarterly report | Aug 5, 2022 | Jun 30, 2022 |
| 8-K |
Current report
Results of operations
|
Aug 5, 2022 | Aug 4, 2022 |
| 11-K | Employee savings plan report | Jun 17, 2022 | Dec 31, 2021 |
| 8-K |
Current report
Shareholder vote results
|
May 24, 2022 | May 19, 2022 |
| 10-Q | Quarterly report | Apr 29, 2022 | Mar 31, 2022 |
| 8-K |
Current report
Results of operations
|
Apr 29, 2022 | Apr 28, 2022 |
| DEFA14A | Additional proxy material | Mar 31, 2022 | — |
| DEF 14A | Proxy statement | Mar 31, 2022 | May 19, 2022 |
| 8-K |
Current report
Material agreement, New debt
|
Mar 4, 2022 | Mar 3, 2022 |
| 8-K |
Current report
Material agreement, New debt, Other events
|
Mar 1, 2022 | Feb 23, 2022 |
| 10-K | Annual report | Feb 18, 2022 | Dec 31, 2021 |
| 8-K |
Current report
Results of operations
|
Feb 18, 2022 | Feb 17, 2022 |
| 8-K |
Current report
Officer or director change
|
Feb 8, 2022 | Feb 4, 2022 |
| 8-K |
Current report
New debt, Bylaw or fiscal year change
|
Dec 21, 2021 | Dec 17, 2021 |
| 8-K |
Current report
Other events
|
Nov 19, 2021 | Nov 16, 2021 |
| 10-Q | Quarterly report | Nov 5, 2021 | Sep 30, 2021 |
| 8-K |
Current report
Results of operations
|
Nov 5, 2021 | Nov 4, 2021 |
| 8-K |
Current report
Other events
|
Nov 4, 2021 | Nov 3, 2021 |
| 8-K |
Current report
Officer or director change
|
Oct 28, 2021 | Oct 26, 2021 |
| 8-K |
Current report
Bylaw or fiscal year change
|
Sep 24, 2021 | Sep 23, 2021 |
| 8-K |
Current report
Other events
|
Sep 16, 2021 | Sep 13, 2021 |
| 10-Q | Quarterly report | Aug 6, 2021 | Jun 30, 2021 |
| 8-K |
Current report
Results of operations
|
Aug 6, 2021 | Aug 5, 2021 |
| 8-K |
Current report
Officer or director change
|
Jul 15, 2021 | Jul 14, 2021 |
| 11-K | Employee savings plan report | Jun 17, 2021 | Dec 31, 2020 |
| 8-K |
Current report
Shareholder vote results
|
May 25, 2021 | May 20, 2021 |
| 10-Q | Quarterly report | May 7, 2021 | Mar 31, 2021 |
| 8-K |
Current report
Results of operations
|
May 7, 2021 | May 6, 2021 |
| DEFA14A | Additional proxy material | Apr 1, 2021 | — |
| DEF 14A | Proxy statement | Apr 1, 2021 | May 20, 2021 |
| 10-K | Annual report | Feb 19, 2021 | Dec 31, 2020 |
| 8-K |
Current report
Results of operations
|
Feb 19, 2021 | Feb 18, 2021 |
| 8-K |
Current report
Officer or director change
|
Jan 29, 2021 | Jan 27, 2021 |
| S-3ASR | Automatic shelf registration | Dec 15, 2020 | — |
| 8-K |
Current report
Material agreement, New debt, Other events
|
Nov 23, 2020 | Nov 17, 2020 |
| S-3ASR | Automatic shelf registration | Nov 6, 2020 | — |
| 10-Q | Quarterly report | Nov 3, 2020 | Sep 30, 2020 |
| 8-K |
Current report
Results of operations
|
Nov 3, 2020 | Nov 2, 2020 |
| 8-K |
Current report
Bylaw or fiscal year change
|
Oct 29, 2020 | Oct 27, 2020 |
| 8-K |
Current report
Regulation FD disclosure
|
Aug 19, 2020 | Aug 18, 2020 |
| 10-Q | Quarterly report | Aug 10, 2020 | Jun 30, 2020 |
| 8-K |
Current report
Results of operations
|
Aug 7, 2020 | Aug 6, 2020 |
| 11-K | Employee savings plan report | Jun 18, 2020 | Dec 31, 2019 |
| 8-K |
Current report
Other events
|
Jun 2, 2020 | May 26, 2020 |
| S-8 | Employee stock plan registration | May 26, 2020 | — |
| 8-K |
Current report
Officer or director change, Shareholder vote results
|
May 22, 2020 | May 21, 2020 |
| 10-Q | Quarterly report | May 8, 2020 | Mar 31, 2020 |
| 8-K |
Current report
Results of operations
|
May 8, 2020 | May 7, 2020 |
| DEFA14A | Additional proxy material | Apr 9, 2020 | — |
| DEF 14A | Proxy statement | Apr 9, 2020 | May 21, 2020 |
| 8-K |
Current report
Results of operations
|
Apr 6, 2020 | Apr 3, 2020 |
| 8-K |
Current report
Other events
|
Apr 2, 2020 | Mar 30, 2020 |
| 8-K |
Current report
Material agreement, New debt
|
Mar 5, 2020 | Mar 3, 2020 |
| 10-K | Annual report | Feb 21, 2020 | Dec 31, 2019 |
| 8-K |
Current report
Results of operations
|
Feb 21, 2020 | Feb 20, 2020 |
| 8-K |
Current report
Officer or director change
|
Dec 13, 2019 | Dec 12, 2019 |
| 8-K |
Current report
Material agreement, Other events
|
Nov 18, 2019 | Nov 14, 2019 |
| 424B2 | Prospectus | Nov 15, 2019 | — |
| 424B5 | Prospectus supplement | Nov 14, 2019 | — |
| 10-Q | Quarterly report | Nov 7, 2019 | Sep 30, 2019 |
| 8-K |
Current report
Results of operations
|
Nov 7, 2019 | Nov 6, 2019 |
| 8-K |
Current report
Other events
|
Sep 26, 2019 | Sep 19, 2019 |
| 10-Q | Quarterly report | Aug 2, 2019 | Jun 30, 2019 |
| 8-K |
Current report
Results of operations
|
Aug 2, 2019 | Aug 1, 2019 |
| 8-K |
Current report
Other events
|
Jun 24, 2019 | Jun 17, 2019 |
| 11-K | Employee savings plan report | Jun 20, 2019 | Dec 31, 2018 |
| 8-K |
Current report
Shareholder vote results
|
May 20, 2019 | May 16, 2019 |
| 10-Q | Quarterly report | May 3, 2019 | Mar 31, 2019 |
| 8-K |
Current report
Results of operations
|
May 3, 2019 | May 2, 2019 |
| DEF 14A | Proxy statement | Apr 8, 2019 | May 16, 2019 |
| 8-K |
Current report
Other events
|
Apr 1, 2019 | Mar 25, 2019 |
| S-8 | Employee stock plan registration | Mar 15, 2019 | — |
| 10-K | Annual report | Feb 22, 2019 | Dec 31, 2018 |
| 8-K |
Current report
Results of operations
|
Feb 22, 2019 | Feb 21, 2019 |
| 8-K |
Current report
Officer or director change
|
Feb 13, 2019 | Feb 11, 2019 |
| CERT | Filing | Dec 31, 2018 | — |
| 8-A12B | Filing | Dec 28, 2018 | — |
| 25 | Filing | Dec 28, 2018 | — |
| 8-K |
Current report
Listing notice, Bylaw or fiscal year change, Other events
|
Dec 18, 2018 | Dec 13, 2018 |
| 8-K |
Current report
Material agreement, Other events
|
Dec 17, 2018 | Dec 13, 2018 |
| 424B2 | Prospectus | Dec 14, 2018 | — |
| 424B5 | Prospectus supplement | Dec 13, 2018 | — |
| 8-K |
Current report
Officer or director change
|
Dec 13, 2018 | Dec 13, 2018 |
| 10-Q | Quarterly report | Nov 7, 2018 | Sep 30, 2018 |
| 8-K |
Current report
Results of operations
|
Nov 7, 2018 | Nov 6, 2018 |
| 8-K |
Current report
Other events
|
Sep 26, 2018 | Sep 19, 2018 |
| 10-Q | Quarterly report | Aug 3, 2018 | Jun 30, 2018 |
| 8-K |
Current report
Results of operations
|
Aug 3, 2018 | Aug 2, 2018 |
Showing 200 filings, the most recent 200. 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.
New to this? Read What Are SEC Filings? 10-K, 10-Q, 8-K and Other Forms Explained.
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)
Other Electric & Other Services Combined companies
- Duke Energy CORP DUK
- Xcel Energy Inc XEL
- Exelon Corp EXC
- Consolidated Edison Inc ED
- PG&E Corp PCG
- Wec Energy Group, Inc. WEC
- Public Service Enterprise Group Inc PEG
- Ameren Corp AEE
Source: SEC EDGAR filings. This is company-reported data, not investment advice.