Borrowings and Other Financing Instruments (Tables)

3 Months Ended

Mar. 31, 2025

Borrowings and Other Financing Instruments [Abstract]

Credit Facilities

As of March 31, 2025, SPS had the following committed revolving credit facility available (in millions of dollars):

Credit Facility (a)		Drawn (b)		Available
$	500	$	209	$	291

(a)Expires in September 2027.

(b)Includes outstanding letters of credit.

Money Pool

Borrowings and Other Financing Instruments [Abstract]

Short-Term Borrowings

Money pool borrowings:

(Amounts in Millions, Except Interest Rates)	Three Months Ended March 31, 2025			Year Ended Dec. 31, 2024
Borrowing limit	$	100		$	100
Amount outstanding at period end	24			7
Average amount outstanding	53			24
Maximum amount outstanding	100			100
Weighted average interest rate, computed on a daily basis	4.28		%	5.29		%
Weighted average interest rate at period end	4.33			4.58

Commercial Paper

Borrowings and Other Financing Instruments [Abstract]

Short-Term Borrowings

Commercial paper outstanding:

(Amounts in Millions, Except Interest Rates)	Three Months Ended March 31, 2025			Year Ended Dec. 31, 2024
Borrowing limit	$	500		$	500
Amount outstanding at period end	209			145
Average amount outstanding	239			35
Maximum amount outstanding	314			160
Weighted average interest rate, computed on a daily basis	4.60		%	5.47		%
Weighted average interest rate at period end	4.67			4.66