Regulatory Matters (Tables)

9 Months Ended

Jun. 30, 2025

Regulated Operations [Abstract]

Schedule of Regulatory Assets and Liabilities

The following regulatory assets and regulatory liabilities were reflected in the balance sheets of the Company, Spire Missouri and Spire Alabama as of June 30, 2025, September 30, 2024, and June 30, 2024.


		June 30,				September 30,				June 30,
Spire		2025				2024				2024
Regulatory Assets:
Current:
Unamortized purchased gas adjustments		$	1.2			$	28.9			$	58.0
Other			33.8				86.5				31.8
Total Current Regulatory Assets			35.0				115.4				89.8
Noncurrent:
Pension and postretirement benefit costs			236.4				237.5				243.2
Cost of removal			687.2				668.2				658.0
Future income taxes due from customers			155.0				150.7				149.0
Energy efficiency			63.7				61.0				59.1
Unamortized purchased gas adjustments			—				1.2				—
Other			151.1				133.2				173.5
Total Noncurrent Regulatory Assets			1,293.4				1,251.8				1,282.8
Total Regulatory Assets		$	1,328.4			$	1,367.2			$	1,372.6
Regulatory Liabilities:
Current:
Unamortized purchased gas adjustments		$	44.0			$	42.3			$	33.3
Other			4.6				7.2				4.6
Total Current Regulatory Liabilities			48.6				49.5				37.9
Noncurrent:
Deferred taxes due to customers			103.7				114.2				117.5
Pension and postretirement benefit costs			261.1				232.9				192.3
Accrued cost of removal			138.3				133.6				135.4
Unamortized purchased gas adjustments			44.8				17.2				83.6
Other			34.1				37.6				18.7
Total Noncurrent Regulatory Liabilities			582.0				535.5				547.5
Total Regulatory Liabilities		$	630.6			$	585.0			$	585.4


		June 30,				September 30,				June 30,
Spire Missouri		2025				2024				2024
Regulatory Assets:
Current:
Unamortized purchased gas adjustments		$	—			$	28.1			$	57.6
Other			8.7				55.9				5.4
Total Current Regulatory Assets			8.7				84.0				63.0
Noncurrent:
Future income taxes due from customers			147.2				142.7				140.8
Pension and postretirement benefit costs			172.5				166.5				177.5
Energy efficiency			63.7				61.0				59.1
Unamortized purchased gas adjustments			—				1.2				—
Cost of removal			91.4				97.0				97.0
Other			138.7				119.6				159.7
Total Noncurrent Regulatory Assets			613.5				588.0				634.1
Total Regulatory Assets		$	622.2			$	672.0			$	697.1
Regulatory Liabilities:
Current:
Unamortized purchased gas adjustments		$	14.0			$	10.2			$	—
Total Current Regulatory Liabilities			14.0				10.2				—
Noncurrent:
Deferred taxes due to customers			92.0				101.8				105.1
Pension and postretirement benefit costs			227.2				196.6				165.7
Accrued cost of removal			96.9				94.5				97.1
Unamortized purchased gas adjustments			44.8				17.2				83.6
Other			30.2				33.2				14.2
Total Noncurrent Regulatory Liabilities			491.1				443.3				465.7
Total Regulatory Liabilities		$	505.1			$	453.5			$	465.7


		June 30,				September 30,				June 30,
Spire Alabama		2025				2024				2024
Regulatory Assets:
Current:
Other		$	13.2			$	19.2			$	14.7
Total Current Regulatory Assets			13.2				19.2				14.7
Noncurrent:
Future income taxes due from customers			1.6				1.8				1.8
Pension and postretirement benefit costs			61.8				68.2				62.3
Cost of removal			595.7				571.2				561.0
Other			0.5				0.8				0.9
Total Noncurrent Regulatory Assets			659.6				642.0				626.0
Total Regulatory Assets		$	672.8			$	661.2			$	640.7
Regulatory Liabilities:
Current:
Unamortized purchased gas adjustments		$	29.3			$	30.9			$	32.2
Other			—				2.9				—
Total Current Regulatory Liabilities			29.3				33.8				32.2
Noncurrent:
Pension and postretirement benefit costs			23.0				25.1				16.4
Other			2.8				3.2				3.2
Total Noncurrent Regulatory Liabilities			25.8				28.3				19.6
Total Regulatory Liabilities		$	55.1			$	62.1			$	51.8

Schedule of Regulatory Assets Not Earning Return

A portion of the Company’s and Spire Missouri’s regulatory assets are not earning a return, as shown in the table below:


		June 30,				September 30,				June 30,
		2025				2024				2024
Spire
Pension and postretirement benefit costs		$	127.2			$	129.7			$	135.9
Future income taxes due from customers			153.4				148.9				147.1
Unamortized purchased gas adjustments			—				29.3				57.6
Other			111.7				132.5				132.3
Total Regulatory Assets Not Earning a Return		$	392.3			$	440.4			$	472.9

Spire Missouri
Pension and postretirement benefit costs		$	127.2			$	129.7			$	135.9
Future income taxes due from customers			147.2				142.7				140.8
Unamortized purchased gas adjustments			—				29.3				57.6
Other			111.7				132.5				132.3
Total Regulatory Assets Not Earning a Return		$	386.1			$	434.2			$	466.6