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Common Equity | 3 Months Ended
--- | ---
Mar. 31, 2024
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2024 | 256,096,848 |
Shareowner Direct Plan | 127,917 |
Equity-based compensation plans | 154,267 |
Shares outstanding, March 31, 2024 | 256,379,032 |
Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 158 |  |  |  |  |  |  |  | 158
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  | 1 |  |  |  | (2)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2024 | $3 |  | $3,033 |  | $3,791 |  | $2 |  | ($12) |  |  |  | $6,817
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  |  |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 163 |  |  |  |  |  |  |  | 163
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  |  |  |  |  | (3)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  |  |  | $6,328
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, March 31, 2024 | $33 |  | $2,937 |  | $1,067 |  |  |  | $4,037
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Ending balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 92 |  |  |  | 92
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, March 31, 2024 | $66 |  | $2,533 |  | $1,396 |  |  |  | $3,995
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  |  |  | $3,491
Net income |  |  |  |  | 88 |  |  |  | 88
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  |  |  | $3,713
IPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2024 | 256,096,848 |
Shareowner Direct Plan | 127,917 |
Equity-based compensation plans | 154,267 |
Shares outstanding, March 31, 2024 | 256,379,032 |
Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 158 |  |  |  |  |  |  |  | 158
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  | 1 |  |  |  | (2)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2024 | $3 |  | $3,033 |  | $3,791 |  | $2 |  | ($12) |  |  |  | $6,817
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  |  |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 163 |  |  |  |  |  |  |  | 163
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  |  |  |  |  | (3)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  |  |  | $6,328
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, March 31, 2024 | $33 |  | $2,937 |  | $1,067 |  |  |  | $4,037
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Ending balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 92 |  |  |  | 92
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, March 31, 2024 | $66 |  | $2,533 |  | $1,396 |  |  |  | $3,995
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  |  |  | $3,491
Net income |  |  |  |  | 88 |  |  |  | 88
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  |  |  | $3,713
WPL [Member] |
Common Equity [Line Items] |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2024 | 256,096,848 |
Shareowner Direct Plan | 127,917 |
Equity-based compensation plans | 154,267 |
Shares outstanding, March 31, 2024 | 256,379,032 |
Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 158 |  |  |  |  |  |  |  | 158
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  | 1 |  |  |  | (2)
Other comprehensive income, net of tax |  |  |  |  |  |  | 1 |  |  |  |  |  | 1
Ending balance, March 31, 2024 | $3 |  | $3,033 |  | $3,791 |  | $2 |  | ($12) |  |  |  | $6,817
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $3 |  | $2,777 |  | $3,509 |  | $— |  | ($13) |  |  |  | $6,276
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 163 |  |  |  |  |  |  |  | 163
Common stock dividends ($0.4525 per share) |  |  |  |  | (113) |  |  |  |  |  |  |  | (113)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | (3) |  |  |  |  |  |  |  |  |  | (3)
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, March 31, 2023 | $3 |  | $2,780 |  | $3,559 |  | ($1) |  | ($13) |  |  |  | $6,328
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 63 |  |  |  | 63
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 50 |  |  |  |  |  | 50
Ending balance, March 31, 2024 | $33 |  | $2,937 |  | $1,067 |  |  |  | $4,037
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $33 |  | $2,807 |  | $968 |  |  |  | $3,808
Net income |  |  |  |  | 72 |  |  |  | 72
Common stock dividends |  |  |  |  | (70) |  |  |  | (70)
Ending balance, March 31, 2023 | $33 |  | $2,807 |  | $970 |  |  |  | $3,810
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended March 31, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 92 |  |  |  | 92
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, March 31, 2024 | $66 |  | $2,533 |  | $1,396 |  |  |  | $3,995
Three Months Ended March 31, 2023 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2022 | $66 |  | $2,233 |  | $1,192 |  |  |  | $3,491
Net income |  |  |  |  | 88 |  |  |  | 88
Common stock dividends |  |  |  |  | (46) |  |  |  | (46)
Capital contributions from parent |  |  | 180 |  |  |  |  |  | 180
Ending balance, March 31, 2023 | $66 |  | $2,413 |  | $1,234 |  |  |  | $3,713

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