Segment Information (Tables)

12 Months Ended

Sep. 30, 2025

Segment Reporting Information [Line Items]

Schedule of Information about Segment Revenue, Segment Expenses and Adjusted Earnings

The following tables present information about Spire’s segment revenue, segment expenses, and Adjusted Earnings.

2025	Gas Utility		Gas Marketing		Midstream		Total Reportable Segments		Other(b)			Intersegment Eliminations			Consolidated
Revenues from external customers	$	2,207.5	$	157.2	$	109.2	$	2,473.9	$	2.5		$	—		$	2,476.4
Intersegment revenues		0.1		-		46.3		46.4		—			(46.4	)		-
Total Operating Revenues		2,207.6		157.2		155.5		2,520.3		2.5			(46.4	)		2,476.4
Less:
Significant segment expenses:
Cost of gas sold, incl. gross receipts taxes		970.9		93.7		3.0		1,067.6		—			(46.4	)		1,021.2
Operation and maintenance expense		467.1		19.4		45.3		531.8		10.3			—			542.1
Depreciation and amortization    expense		277.6		1.0		19.2		297.8		0.4			—			298.2
Interest expense		137.1		—		11.6		148.7		55.4			—			204.1
Income tax expense (benefit)		47.4		11.1		15.7		74.2		(14.5	)		—			59.7
Other segment items (a)		76.1		6.1		4.4		86.6		(11.0	)		—			75.6
Adjusted earnings (loss) [Non-GAAP]	$	231.4	$	25.9	$	56.3	$	313.6	$	(38.1	)	$	-		$	275.5
Capital expenditures		816.8		0.1		106.8		923.7		(1.3	)		—			922.4

2024	Gas Utility		Gas Marketing		Midstream		Total Reportable Segments		Other(b)			Intersegment Eliminations			Consolidated
Revenues from external customers	$	2,436.2	$	99.2	$	56.9	$	2,592.3	$	0.7		$	—		$	2,593.0
Intersegment revenues		1.7		—		43.8		45.5		-			(45.5	)		-
Total Operating Revenues		2,437.9		99.2		100.7		2,637.8		0.7			(45.5	)		2,593.0
Less:
Significant segment expenses:
Cost of gas sold, incl. gross receipts taxes		1,238.7		37.1		1.1		1,276.9		0.1			(45.5	)		1,231.5
Operation and maintenance expense		452.8		18.2		34.7		505.7		1.7			—			507.4
Depreciation and amortization    expense		263.6		1.5		12.8		277.9		0.5			—			278.4
Interest expense		147.3		—		7.0		154.3		46.8			—			201.1
Income tax expense (benefit)		48.0		10.8		9.6		68.4		(9.7	)		—			58.7
Other segment items (a)		66.7		8.2		2.0		76.9		(8.4	)		—			68.5
Adjusted earnings (loss) [Non-GAAP]	$	220.8	$	23.4	$	33.5	$	277.7	$	(30.3	)	$	-		$	247.4
Capital expenditures		691.1		0.1		171.3		862.5		(1.2	)		—			861.3

2023	Gas Utility		Gas Marketing			Midstream		Total Reportable Segments		Other(b)			Intersegment Eliminations			Consolidated
Revenues from external customers	$	2,456.6	$	179.1		$	29.9	$	2,665.6	$	0.7		$	—		$	2,666.3
Intersegment revenues		0.3		—			36.2		36.5		—			(36.5	)		-
Total Operating Revenues		2,456.9		179.1			66.1		2,702.1		0.7			(36.5	)		2,666.3
Less:
Significant segment expenses:
Cost of gas sold, incl. gross receipts taxes		1,321.1		108.0			—		1,429.1		—			(36.5	)		1,392.6
Operation and maintenance expense		461.8		19.4			30.5		511.7		5.9			—			517.6
Depreciation and amortization    expense		244.4		1.5			8.4		254.3		0.5			—			254.8
Interest expense		139.9		—			8.6		148.5		37.2			—			185.7
Income tax expense (benefit)		32.7		12.8			3.8		49.3		(10.5	)		—			38.8
Other segment items (a)		56.5		(10.2	)		0.7		47.0		1.7			—			48.7
Adjusted earnings (loss)	$	200.5	$	47.6		$	14.1	$	262.2	$	(34.1	)	—			$	228.1
Capital expenditures		588.6		0.4			73.6		662.6		(0.1	)		—			662.5

(a) Other segment items for each reportable segment include fair value and timing adjustments, acquisition and restructuring activities, taxes other than income and gross receipt taxes, and miscellaneous income and deductions.

(b) All other components of the Company's consolidated information include Spire's subsidiaries engaged in the operation of a propane pipeline and risk management, among other activities, and unallocated corporate items, including certain debt and associated interest costs.

Reconciliation Of Consolidated Net Economic Earnings To Consolidated Net Income

Reconciliation of Consolidated Net Income to Consolidated Adjusted Earnings	2025			2024			2023
Net Income	$	271.7		$	250.9		$	217.5
Adjustments, pre-tax:
Fair value and timing adjustments		(10.4	)		(12.4	)		11.4
Acquisition and restructuring activities		15.2			7.6			2.5
Income tax adjustments		(1.0	)		1.3			(3.3	)
Adjusted Earnings	$	275.5		$	247.4		$	228.1

Spire Missouri [Member]

Segment Reporting Information [Line Items]

Schedule of Financial Data Related to Gross Receipt Taxes and Capital Expenditures

Financial data related to gross receipt taxes and capital expenditures are as follows:

	2025		2024		2023
Gross Receipt Taxes	$	82.9	$	93.1	$	96.7
Capital Expenditures		641.2		553.0		447.5

Spire Alabama Inc [Member]

Segment Reporting Information [Line Items]

Schedule of Financial Data Related to Gross Receipt Taxes and Capital Expenditures

Financial data related to gross receipt taxes and capital expenditures are as follows:

	2025		2024		2023
Gross Receipt Taxes		27.9		30.1		29.9
Capital Expenditures		144.2		112.8		117.6