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Common Equity (Tables) | 9 Months Ended
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Sep. 30, 2025
Schedule of Capitalization, Equity [Line Items] |
Common Share Activity | A summary of Alliant Energy’s common stock activity was as follows:
Shares outstanding, January 1, 2025 | 256,690,222 |
Shareowner Direct Plan | 277,090 |
Equity-based compensation plans | 86,377 |
Shares outstanding, September 30, 2025 | 257,053,689 |
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 September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $3 |  | $3,075 |  | $4,080 |  | $— |  | ($13) |  |  |  | $7,145
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 281 |  |  |  |  |  |  |  | 281
Common stock dividends ($0.5075 per share) |  |  |  |  | (130) |  |  |  |  |  |  |  | (130)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  | (1) |  |  |  | 5
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $3 |  | $3,042 |  | $3,755 |  | $3 |  | ($12) |  |  |  | $6,791
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 295 |  |  |  |  |  |  |  | 295
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive loss, net of tax |  |  |  |  |  |  | (4) |  |  |  |  |  | (4)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $3 |  | $3,060 |  | $3,954 |  | $1 |  | ($14) |  |  |  | $7,004
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 668 |  |  |  |  |  |  |  | 668
Common stock dividends ($1.5225 per share) |  |  |  |  | (391) |  |  |  |  |  |  |  | (391)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 9 |  |  |  |  |  |  |  |  |  | 9
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 540 |  |  |  |  |  |  |  | 540
Common stock dividends ($1.44 per share) |  |  |  |  | (369) |  |  |  |  |  |  |  | (369)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $33 |  | $3,357 |  | $1,245 |  |  |  | $4,635
Net income |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (90) |  |  |  | (90)
Capital contributions from parent |  |  | 140 |  |  |  |  |  | 140
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $33 |  | $3,012 |  | $1,035 |  |  |  | $4,080
Net income |  |  |  |  | 190 |  |  |  | 190
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 200 |  |  |  |  |  | 200
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $33 |  | $3,212 |  | $1,216 |  |  |  | $4,461
Net income |  |  |  |  | 374 |  |  |  | 374
Common stock dividends |  |  |  |  | (270) |  |  |  | (270)
Capital contributions from parent |  |  | 285 |  |  |  |  |  | 285
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 272 |  |  |  | 272
Common stock dividends |  |  |  |  | (151) |  |  |  | (151)
Capital contributions from parent |  |  | 325 |  |  |  |  |  | 325
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $66 |  | $2,533 |  | $1,581 |  |  |  | $4,180
Net income |  |  |  |  | 123 |  |  |  | 123
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $66 |  | $2,533 |  | $1,411 |  |  |  | $4,010
Net income |  |  |  |  | 114 |  |  |  | 114
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $66 |  | $2,533 |  | $1,502 |  |  |  | $4,101
Net income |  |  |  |  | 321 |  |  |  | 321
Common stock dividends |  |  |  |  | (163) |  |  |  | (163)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 270 |  |  |  | 270
Common stock dividends |  |  |  |  | (147) |  |  |  | (147)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075
IPL [Member] |
Schedule of Capitalization, Equity [Line Items] |
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 September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $3 |  | $3,075 |  | $4,080 |  | $— |  | ($13) |  |  |  | $7,145
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 281 |  |  |  |  |  |  |  | 281
Common stock dividends ($0.5075 per share) |  |  |  |  | (130) |  |  |  |  |  |  |  | (130)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  | (1) |  |  |  | 5
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $3 |  | $3,042 |  | $3,755 |  | $3 |  | ($12) |  |  |  | $6,791
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 295 |  |  |  |  |  |  |  | 295
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive loss, net of tax |  |  |  |  |  |  | (4) |  |  |  |  |  | (4)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $3 |  | $3,060 |  | $3,954 |  | $1 |  | ($14) |  |  |  | $7,004
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 668 |  |  |  |  |  |  |  | 668
Common stock dividends ($1.5225 per share) |  |  |  |  | (391) |  |  |  |  |  |  |  | (391)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 9 |  |  |  |  |  |  |  |  |  | 9
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 540 |  |  |  |  |  |  |  | 540
Common stock dividends ($1.44 per share) |  |  |  |  | (369) |  |  |  |  |  |  |  | (369)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $33 |  | $3,357 |  | $1,245 |  |  |  | $4,635
Net income |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (90) |  |  |  | (90)
Capital contributions from parent |  |  | 140 |  |  |  |  |  | 140
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $33 |  | $3,012 |  | $1,035 |  |  |  | $4,080
Net income |  |  |  |  | 190 |  |  |  | 190
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 200 |  |  |  |  |  | 200
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $33 |  | $3,212 |  | $1,216 |  |  |  | $4,461
Net income |  |  |  |  | 374 |  |  |  | 374
Common stock dividends |  |  |  |  | (270) |  |  |  | (270)
Capital contributions from parent |  |  | 285 |  |  |  |  |  | 285
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 272 |  |  |  | 272
Common stock dividends |  |  |  |  | (151) |  |  |  | (151)
Capital contributions from parent |  |  | 325 |  |  |  |  |  | 325
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $66 |  | $2,533 |  | $1,581 |  |  |  | $4,180
Net income |  |  |  |  | 123 |  |  |  | 123
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $66 |  | $2,533 |  | $1,411 |  |  |  | $4,010
Net income |  |  |  |  | 114 |  |  |  | 114
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $66 |  | $2,533 |  | $1,502 |  |  |  | $4,101
Net income |  |  |  |  | 321 |  |  |  | 321
Common stock dividends |  |  |  |  | (163) |  |  |  | (163)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 270 |  |  |  | 270
Common stock dividends |  |  |  |  | (147) |  |  |  | (147)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075
WPL [Member] |
Schedule of Capitalization, Equity [Line Items] |
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 September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $3 |  | $3,075 |  | $4,080 |  | $— |  | ($13) |  |  |  | $7,145
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 281 |  |  |  |  |  |  |  | 281
Common stock dividends ($0.5075 per share) |  |  |  |  | (130) |  |  |  |  |  |  |  | (130)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 6 |  |  |  |  |  | (1) |  |  |  | 5
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $3 |  | $3,042 |  | $3,755 |  | $3 |  | ($12) |  |  |  | $6,791
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 295 |  |  |  |  |  |  |  | 295
Common stock dividends ($0.48 per share) |  |  |  |  | (123) |  |  |  |  |  |  |  | (123)
Shareowner Direct Plan issuances |  |  | 6 |  |  |  |  |  |  |  |  |  | 6
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  | (1) |  |  |  | 3
Other comprehensive loss, net of tax |  |  |  |  |  |  | (4) |  |  |  |  |  | (4)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
Alliant Energy |  |  |  |  |  |  | Accumulated |  | Shares in |  |  |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  |  |  | Common
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $3 |  | $3,060 |  | $3,954 |  | $1 |  | ($14) |  |  |  | $7,004
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 668 |  |  |  |  |  |  |  | 668
Common stock dividends ($1.5225 per share) |  |  |  |  | (391) |  |  |  |  |  |  |  | (391)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 9 |  |  |  |  |  |  |  |  |  | 9
Other comprehensive loss, net of tax |  |  |  |  |  |  | (1) |  |  |  |  |  | (1)
Ending balance, September 30, 2025 | $3 |  | $3,087 |  | $4,231 |  | $— |  | ($14) |  |  |  | $7,307
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $3 |  | $3,030 |  | $3,756 |  | $1 |  | ($13) |  |  |  | $6,777
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 540 |  |  |  |  |  |  |  | 540
Common stock dividends ($1.44 per share) |  |  |  |  | (369) |  |  |  |  |  |  |  | (369)
Shareowner Direct Plan issuances |  |  | 18 |  |  |  |  |  |  |  |  |  | 18
Equity-based compensation plans and other |  |  | 4 |  |  |  |  |  |  |  |  |  | 4
Other comprehensive loss, net of tax |  |  |  |  |  |  | (2) |  |  |  |  |  | (2)
Ending balance, September 30, 2024 | $3 |  | $3,052 |  | $3,927 |  | ($1) |  | ($13) |  |  |  | $6,968
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $33 |  | $3,357 |  | $1,245 |  |  |  | $4,635
Net income |  |  |  |  | 165 |  |  |  | 165
Common stock dividends |  |  |  |  | (90) |  |  |  | (90)
Capital contributions from parent |  |  | 140 |  |  |  |  |  | 140
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $33 |  | $3,012 |  | $1,035 |  |  |  | $4,080
Net income |  |  |  |  | 190 |  |  |  | 190
Common stock dividends |  |  |  |  | (50) |  |  |  | (50)
Capital contributions from parent |  |  | 200 |  |  |  |  |  | 200
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
IPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $33 |  | $3,212 |  | $1,216 |  |  |  | $4,461
Net income |  |  |  |  | 374 |  |  |  | 374
Common stock dividends |  |  |  |  | (270) |  |  |  | (270)
Capital contributions from parent |  |  | 285 |  |  |  |  |  | 285
Ending balance, September 30, 2025 | $33 |  | $3,497 |  | $1,320 |  |  |  | $4,850
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $33 |  | $2,887 |  | $1,054 |  |  |  | $3,974
Net income |  |  |  |  | 272 |  |  |  | 272
Common stock dividends |  |  |  |  | (151) |  |  |  | (151)
Capital contributions from parent |  |  | 325 |  |  |  |  |  | 325
Ending balance, September 30, 2024 | $33 |  | $3,212 |  | $1,175 |  |  |  | $4,420
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Three Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2025 | $66 |  | $2,533 |  | $1,581 |  |  |  | $4,180
Net income |  |  |  |  | 123 |  |  |  | 123
Common stock dividends |  |  |  |  | (44) |  |  |  | (44)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Three Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, June 30, 2024 | $66 |  | $2,533 |  | $1,411 |  |  |  | $4,010
Net income |  |  |  |  | 114 |  |  |  | 114
Common stock dividends |  |  |  |  | (49) |  |  |  | (49)
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075
WPL |  |  | Additional |  |  |  |  |  | Total
| Common |  | Paid-In |  | Retained |  |  |  | Common
| Stock |  | Capital |  | Earnings |  |  |  | Equity
Nine Months Ended September 30, 2025 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2024 | $66 |  | $2,533 |  | $1,502 |  |  |  | $4,101
Net income |  |  |  |  | 321 |  |  |  | 321
Common stock dividends |  |  |  |  | (163) |  |  |  | (163)
Capital contributions from parent |  |  | 80 |  |  |  |  |  | 80
Ending balance, September 30, 2025 | $66 |  | $2,613 |  | $1,660 |  |  |  | $4,339
Nine Months Ended September 30, 2024 |  |  |  |  |  |  |  |  |
Beginning balance, December 31, 2023 | $66 |  | $2,478 |  | $1,353 |  |  |  | $3,897
Net income |  |  |  |  | 270 |  |  |  | 270
Common stock dividends |  |  |  |  | (147) |  |  |  | (147)
Capital contributions from parent |  |  | 55 |  |  |  |  |  | 55
Ending balance, September 30, 2024 | $66 |  | $2,533 |  | $1,476 |  |  |  | $4,075

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