Debt (Tables)

6 Months Ended

Jun. 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):

June 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$399	$—	$222
Weighted average interest rates	1.8%	N/A	1.7%
Available credit facility capacity	$601	$250	$78

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$441	$571	$—	$19	$222	$232
Average amount outstanding (based on daily outstanding balances)	$337	$452	$—	$1	$166	$177
Weighted average interest rates	1.0%	0.2%	—%	0.2%	0.9%	0.1%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$578	$—	$19	$252	$275
Average amount outstanding (based on daily outstanding balances)	$390	$438	$—	$—	$185	$183
Weighted average interest rates	0.6%	0.2%	—%	0.2%	0.5%	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):

June 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$399	$—	$222
Weighted average interest rates	1.8%	N/A	1.7%
Available credit facility capacity	$601	$250	$78

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$441	$571	$—	$19	$222	$232
Average amount outstanding (based on daily outstanding balances)	$337	$452	$—	$1	$166	$177
Weighted average interest rates	1.0%	0.2%	—%	0.2%	0.9%	0.1%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$578	$—	$19	$252	$275
Average amount outstanding (based on daily outstanding balances)	$390	$438	$—	$—	$185	$183
Weighted average interest rates	0.6%	0.2%	—%	0.2%	0.5%	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):

June 30, 2022	Alliant Energy	IPL	WPL
Amount outstanding	$399	$—	$222
Weighted average interest rates	1.8%	N/A	1.7%
Available credit facility capacity	$601	$250	$78

	Alliant Energy		IPL		WPL
Three Months Ended June 30	2022	2021	2022	2021	2022	2021
Maximum amount outstanding (based on daily outstanding balances)	$441	$571	$—	$19	$222	$232
Average amount outstanding (based on daily outstanding balances)	$337	$452	$—	$1	$166	$177
Weighted average interest rates	1.0%	0.2%	—%	0.2%	0.9%	0.1%
Six Months Ended June 30
Maximum amount outstanding (based on daily outstanding balances)	$577	$578	$—	$19	$252	$275
Average amount outstanding (based on daily outstanding balances)	$390	$438	$—	$—	$185	$183
Weighted average interest rates	0.6%	0.2%	—%	0.2%	0.5%	0.1%