The composition of long-term debt as of September 30 is shown in the following tables.

	2020			2019
Spire
2.52% Senior Notes, due September 1, 2021	$	35.0		$	35.0
3.31% Notes Payable, due December 15, 2022		25.0			25.0
3.54% Senior Notes, due February 27, 2024		150.0			150.0
3.13% Senior Notes, due September 1, 2026		130.0			130.0
3.93% Senior Notes, due March 15, 2027		100.0			100.0
4.70% Senior Notes, due August 15, 2044		250.0			250.0
Total principal of Spire Missouri long-term debt (see below)		1,098.0			930.0
Total principal of Spire Alabama long-term debt (see below)		475.0			415.0
Other subsidiaries' long-term debt:
4.14% First Mortgage Bonds, due September 30, 2021		20.0			20.0
5.00% First Mortgage Bonds, due September 30, 2031		42.0			42.0
2.95% Notes, with annual principal payments through December 2034		135.0			—
3.52% First Mortgage Bonds, due September 30, 2049		40.0			40.0
Total principal of long-term debt		2,500.0			2,137.0
Less: Unamortized discounts and debt issuance costs		(15.9	)		(14.4	)
Less: Current portion		(60.4	)		(40.0	)
Long-term debt, excluding current portion	$	2,423.7		$	2,082.6
Spire Missouri
Floating-rate note due December 1, 2021	$	—		$	100.0
First Mortgage Bonds:
3.00% Series, due March 15, 2023		55.0			55.0
3.40% Series, due August 15, 2023		250.0			250.0
3.40% Series, due March 15, 2028		45.0			45.0
7.00% Series, due June 1, 2029		19.3			25.0
2.84% Series, due November 15, 2029		275.0			—
7.90% Series, due September 15, 2030		30.0			30.0
3.68% Series, due September 15, 2032		50.0			50.0
6.00% Series, due May 1, 2034		99.3			100.0
6.15% Series, due June 1, 2036		54.5			55.0
4.63% Series, due August 15, 2043		99.9			100.0
4.23% Series, due September 15, 2047		70.0			70.0
4.38% Series, due September 15, 2057		50.0			50.0
Total principal of Spire Missouri long-term debt		1,098.0			930.0
Less: Unamortized discounts and debt issuance costs		(6.0	)		(5.0	)
Less: Current portion		—			—
Spire Missouri long-term debt, excluding current portion	$	1,092.0		$	925.0
Spire Alabama
5.20% Notes, due January 15, 2020	$	—		$	40.0
3.86% Notes, due December 22, 2021		50.0			50.0
3.21% Notes, due September 15, 2025		35.0			35.0
2.88% Notes, due December 1, 2029		100.0			—
5.90% Notes, due January 15, 2037		45.0			45.0
4.31% Notes, due December 1, 2045		80.0			80.0
3.92% Notes, due January 15, 2048		45.0			45.0
4.64% Notes, due January 15, 2049		90.0			90.0
4.02% Notes, due January 15, 2058		30.0			30.0
Total principal of Spire Alabama long-term debt		475.0			415.0
Less: Unamortized discounts and debt issuance costs		(3.2	)		(2.8	)
Less: Current portion		—			(40.0	)
Spire Alabama long-term debt, excluding current portion	$	471.8		$	372.2

Maturities of long-term debt for Spire on a consolidated basis, Spire Missouri and Spire Alabama for the five fiscal years after September 30, 2020 are as follows:

The long-term debt agreements of Spire, Spire Missouri and Spire Alabama contain customary financial covenants and default provisions. As of September 30, 2020, there were no events of default under these financial covenants.

At September 30, 2020, including the current portion but excluding unamortized discounts and debt issuance costs, Spire had long-term debt totaling $2,500.0, of which $1,098.0 was issued by Spire Missouri, $475.0 was issued by Spire Alabama and $237.0 was issued by other subsidiaries. All long-term debt bears fixed rates and is subject to changes in fair value as market interest rates change. However, increases and decreases in fair value would impact earnings and cash flows only if the Company were to reacquire any of these issues in the open market prior to maturity. Under GAAP applicable to the Utilities’ regulated operations, losses or gains on early redemption of long-term debt would typically be deferred as regulatory assets or regulatory liabilities and amortized over a future period. Interest expense shown on Spire’s consolidated statement of income is net of capitalized interest totaling $5.8, $6.8 and $2.6 for the years ended September 30, 2020, 2019 and 2018, respectively.

As indicated in Note 5, Shareholders’ Equity, Spire has a shelf registration statement on Form S-3 on file with the SEC for the issuance of equity and debt securities.

At September 30, 2020, including the current portion (none) but excluding unamortized discounts and debt issuance costs, Spire Missouri had long-term debt totaling $1,098.0. All long-term debt bears fixed rates and is subject to changes in fair value as market interest rates change. Interest expense shown on Spire Missouri’s statement of comprehensive income is net of capitalized interest totaling $0.8, $1.9 and $0.9 for the years ended September 30, 2020, 2019 and 2018, respectively.

As indicated in Note 5, Shareholders’ Equity, Spire Missouri has a shelf registration on Form S-3 on file with the SEC for issuance of first mortgage bonds, unsecured debt and preferred stock, which expires on May 14, 2022. Spire Missouri was authorized by the MoPSC to issue registered securities (first mortgage bonds, unsecured debt and preferred stock), common stock, and private placement debt in an aggregate amount of up to $500.0 for financings placed any time before September 30, 2021. As of September 30, 2020, $125.0 remained available under this authorization.

Substantially all of Spire Missouri’s plant is subject to the liens of its first mortgage bonds. The mortgage contains several restrictions on Spire Missouri’s ability to pay cash dividends on its common stock, which are described in Note 5, Shareholders’ Equity.

At September 30, 2020, including the current portion but excluding unamortized debt issuance costs, Spire Alabama had fixed-rate long-term debt totaling $475.0. While these long-term debt issues are fixed-rate, they are subject to changes in fair value as market interest rates change. Interest expense shown on Spire Alabama’s statement of income is net of capitalized interest totaling $1.9 for the year ended September 30, 2020.

Because Spire Alabama has no standing authority to issue long-term debt, it must petition the APSC for each planned issuance. On March 24, 2020, the APSC approved an application for up to $150.0 of additional long-term debt financing.