Debt (Tables)

9 Months Ended

Sep. 30, 2022

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):

September 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$383	$—	$—
Weighted average interest rates	3.4%	N/A	N/A
Available credit facility capacity	$617	$250	$300

	Alliant Energy		IPL		WPL
Three Months Ended September 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$449	$648	$—	$8	$251	$320
Average amount outstanding (based on daily outstanding balances)	$353	$560	$—	$—	$110	$221
Weighted average interest rates	2.4%	0.2%	—%	0.2%	2.0%	0.1%
Nine Months Ended September 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$648	$—	$19	$252	$320
Average amount outstanding (based on daily outstanding balances)	$377	$479	$—	$—	$160	$196
Weighted average interest rates	1.2%	0.2%	—%	0.2%	0.9%	0.1%

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):

September 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$383	$—	$—
Weighted average interest rates	3.4%	N/A	N/A
Available credit facility capacity	$617	$250	$300

	Alliant Energy		IPL		WPL
Three Months Ended September 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$449	$648	$—	$8	$251	$320
Average amount outstanding (based on daily outstanding balances)	$353	$560	$—	$—	$110	$221
Weighted average interest rates	2.4%	0.2%	—%	0.2%	2.0%	0.1%
Nine Months Ended September 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$648	$—	$19	$252	$320
Average amount outstanding (based on daily outstanding balances)	$377	$479	$—	$—	$160	$196
Weighted average interest rates	1.2%	0.2%	—%	0.2%	0.9%	0.1%

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):

September 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$383	$—	$—
Weighted average interest rates	3.4%	N/A	N/A
Available credit facility capacity	$617	$250	$300

	Alliant Energy		IPL		WPL
Three Months Ended September 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$449	$648	$—	$8	$251	$320
Average amount outstanding (based on daily outstanding balances)	$353	$560	$—	$—	$110	$221
Weighted average interest rates	2.4%	0.2%	—%	0.2%	2.0%	0.1%
Nine Months Ended September 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$648	$—	$19	$252	$320
Average amount outstanding (based on daily outstanding balances)	$377	$479	$—	$—	$160	$196
Weighted average interest rates	1.2%	0.2%	—%	0.2%	0.9%	0.1%