Debt (Tables)

6 Months Ended

Jun. 30, 2023

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):

June 30, 2023	Alliant Energy	IPL	WPL
Amount outstanding	$391	$—	$44
Weighted average interest rates	5.3%	—%	5.2%
Available credit facility capacity (a)	$554	$195	$256

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2023	2022	2023	2022	2023	2022
Maximum amount outstanding (based on daily outstanding balances)	$391	$441	$70	$—	$91	$222
Average amount outstanding (based on daily outstanding balances)	$88	$337	$6	$—	$18	$166
Weighted average interest rates	5.3%	1.0%	5.3%	—%	5.2%	0.9%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$793	$577	$70	$—	$349	$252
Average amount outstanding (based on daily outstanding balances)	$330	$390	$3	$—	$160	$185
Weighted average interest rates	4.8%	0.6%	5.3%	—%	4.8%	0.5%

(a)Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2023.

IPL [Member]

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):

June 30, 2023	Alliant Energy	IPL	WPL
Amount outstanding	$391	$—	$44
Weighted average interest rates	5.3%	—%	5.2%
Available credit facility capacity (a)	$554	$195	$256

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2023	2022	2023	2022	2023	2022
Maximum amount outstanding (based on daily outstanding balances)	$391	$441	$70	$—	$91	$222
Average amount outstanding (based on daily outstanding balances)	$88	$337	$6	$—	$18	$166
Weighted average interest rates	5.3%	1.0%	5.3%	—%	5.2%	0.9%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$793	$577	$70	$—	$349	$252
Average amount outstanding (based on daily outstanding balances)	$330	$390	$3	$—	$160	$185
Weighted average interest rates	4.8%	0.6%	5.3%	—%	4.8%	0.5%

(a)Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2023.

WPL [Member]

Short-term Debt [Line Items]

Other Short-Term Borrowings

Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper classified as short-term debt was as follows (dollars in millions):

June 30, 2023	Alliant Energy	IPL	WPL
Amount outstanding	$391	$—	$44
Weighted average interest rates	5.3%	—%	5.2%
Available credit facility capacity (a)	$554	$195	$256

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2023	2022	2023	2022	2023	2022
Maximum amount outstanding (based on daily outstanding balances)	$391	$441	$70	$—	$91	$222
Average amount outstanding (based on daily outstanding balances)	$88	$337	$6	$—	$18	$166
Weighted average interest rates	5.3%	1.0%	5.3%	—%	5.2%	0.9%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$793	$577	$70	$—	$349	$252
Average amount outstanding (based on daily outstanding balances)	$330	$390	$3	$—	$160	$185
Weighted average interest rates	4.8%	0.6%	5.3%	—%	4.8%	0.5%

(a)Alliant Energy’s and IPL’s available credit facility capacities reflect outstanding commercial paper classified as both short- and long-term debt at June 30, 2023.