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Long-Term Debt And Equity Financings | 12 Months Ended
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Dec. 31, 2025
Long-Term Debt And Equity Financings [Abstract] |
LONG-TERM DEBT AND EQUITY FINANCINGS | LONG-TERM DEBT AND EQUITY FINANCINGS The following table presents long-term debt outstanding, including maturities due within one year, as of December 31, 2025 and 2024:
| 2025 |  | 2024
Ameren (Parent): |  |  |
3.65% Senior unsecured notes due 2026 | 350 |  |  | 350 |
5.70% Senior unsecured notes due 2026 | 600 |  |  | 600 |
1.95% Senior unsecured notes due 2027 | 500 |  |  | 500 |
1.75% Senior unsecured notes due 2028 | 450 |  |  | 450 |
5.00% Senior unsecured notes due 2029 | 700 |  |  | 700 |
3.50% Senior unsecured notes due 2031 | 800 |  |  | 800 |
5.375% Senior unsecured debt due 2035 | 750 |  |  | — |
Total long-term debt, gross | 4,150 |  |  | 3,400 |
Less: Unamortized discount and premium | (3) |  |  | (3) |
Less: Unamortized debt issuance costs | (16) |  |  | (14) |
Less: Maturities due within one year | (950) |  |  | — |
Long-term debt, net | $ | 3,181 |  |  | $ | 3,383 |
Ameren Missouri: |  |  |
Bonds and notes: |  |  |
2.95% Senior secured notes due 2027(a) | $ | 400 |  |  | $ | 400 |
3.50% First mortgage bonds due 2029(b) | 450 |  |  | 450 |
2.95% First mortgage bonds due 2030(b) | 465 |  |  | 465 |
2.15% First mortgage bonds due 2032(b) | 525 |  |  | 525 |
2.90% 1998 Series A bonds due 2033(c) | 60 |  |  | 60 |
2.90% 1998 Series B bonds due 2033(c) | 50 |  |  | 50 |
2.75% 1998 Series C bonds due 2033(c) | 50 |  |  | 50 |
5.20% First mortgage bonds due 2034(b) | 500 |  |  | 500 |
5.50% Senior secured notes due 2034(a) | 184 |  |  | 184 |
5.25% First mortgage bonds due 2035(b) | 500 |  |  | — |
5.30% Senior secured notes due 2037(a) | 300 |  |  | 300 |
8.45% Senior secured notes due 2039(a)(d) | 350 |  |  | 350 |
4.85% Securitized utility tariff bonds due 2039(e) | 459 |  |  | 476 |
3.90% Senior secured notes due 2042(a)(d) | 485 |  |  | 485 |
3.65% Senior secured notes due 2045(a) | 400 |  |  | 400 |
4.00% First mortgage bonds due 2048(b) | 425 |  |  | 425 |
3.25% First mortgage bonds due 2049(b) | 330 |  |  | 330 |
2.625% First mortgage bonds due 2051(b) | 550 |  |  | 550 |
3.90% First mortgage bonds due 2052(b) | 525 |  |  | 525 |
5.45% First mortgage bonds due 2053(b) | 500 |  |  | 500 |
5.25% First mortgage bonds due 2054(b) | 350 |  |  | 350 |
5.125% First mortgage bonds due 2055(b) | 450 |  |  | 450 |
Total long-term debt, gross | 8,308 |  |  | 7,825 |
Less: Long-term debt – related parties, gross | (88) |  |  | (58) |
Less: Unamortized discount and premium | (15) |  |  | (17) |
Less: Unamortized debt issuance costs | (62) |  |  | (62) |
Less: Maturities due within one year | (23) |  |  | (17) |
Long-term debt, net | $ | 8,120 |  |  | $ | 7,671 |
| 2025 |  | 2024
Ameren Illinois: |  |  |
Bonds and notes: |  |  |
3.25% Senior secured notes due 2025(f) | — |  |  | 300 |
6.125% Senior secured notes due 2028(f) | 60 |  |  | 60 |
3.80% First mortgage bonds due 2028(g) | 430 |  |  | 430 |
1.55% First mortgage bonds due 2030(g) | 375 |  |  | 375 |
3.85% First mortgage bonds due 2032(g) | 500 |  |  | 500 |
4.95% First mortgage bonds due 2033(g) | 500 |  |  | 500 |
6.70% Senior secured notes due 2036(f) | 61 |  |  | 61 |
6.70% Senior secured notes due 2036(f) | 42 |  |  | 42 |
4.80% Senior secured notes due 2043(f) | 280 |  |  | 280 |
4.30% Senior secured notes due 2044(f) | 250 |  |  | 250 |
4.15% Senior secured notes due 2046(f) | 490 |  |  | 490 |
3.70% First mortgage bonds due 2047(g) | 500 |  |  | 500 |
4.50% First mortgage bonds due 2049(g) | 500 |  |  | 500 |
3.25% First mortgage bonds due 2050(g) | 300 |  |  | 300 |
2.90% First mortgage bonds due 2051(g) | 350 |  |  | 350 |
5.90% First mortgage bonds due 2052(g) | 350 |  |  | 350 |
5.55% First mortgage bonds due 2054(g) | 625 |  |  | 625 |
5.625% First mortgage bonds due 2055(g) | 700 |  |  | — |
Total long-term debt, gross | 6,313 |  |  | 5,913 |
Less: Long-term debt – related parties, gross | (5) |  |  | (3) |
Less: Unamortized discount and premium | 2 |  |  | (10) |
Less: Unamortized debt issuance costs | (56) |  |  | (51) |
Less: Maturities due within one year | — |  |  | (300) |
Long-term debt, net | $ | 6,254 |  |  | $ | 5,549 |
ATXI: |  |  |
2.45% Senior unsecured notes due 2036(h) | $ | 75 |  |  | $ | 75 |
5.17% Senior unsecured notes due 2039 | 70 |  |  | 70 |
3.43% Senior unsecured notes due 2050(i) | 351 |  |  | 351 |
2.96% Senior unsecured notes due 2052(j) | 95 |  |  | 95 |
5.42% Senior unsecured notes due 2053 | 70 |  |  | 70 |
Total long-term debt, gross | 661 |  |  | 661 |
Less: Unamortized debt issuance costs | (2) |  |  | (2) |
Long-term debt, net | $ | 659 |  |  | $ | 659 |
Ameren consolidated long-term debt, net | $ | 18,214 |  |  | $ | 17,262 |
(a)These notes are collaterally secured by first mortgage bonds issued by Ameren Missouri under the Ameren Missouri mortgage indenture. The notes have a fall-away lien provision and will remain secured only as long as any first mortgage bonds issued under the Ameren Missouri mortgage indenture remain outstanding. Redemption, purchase, or maturity of all first mortgage bonds, including first mortgage bonds currently outstanding and any that may be issued in the future, would result in a release of the first mortgage bonds currently securing these notes, at which time these notes would become unsecured obligations. Considering the 2055 maturity date of the 5.125% first mortgage bonds and the restrictions preventing a release date to occur that are attached to certain senior secured notes described in footnote (d) below, Ameren Missouri does not expect the first mortgage lien protection associated with these notes to fall away. (b)These bonds are first mortgage bonds issued by Ameren Missouri under the Ameren Missouri mortgage indenture. They are secured by substantially all Ameren Missouri property and franchises. (c)These bonds are collaterally secured by first mortgage bonds issued by Ameren Missouri under the Ameren Missouri mortgage indenture and have a fall-away lien provision similar to that of Ameren Missouri’s senior secured notes. (d)Ameren Missouri has agreed that so long as any of the 3.90% senior secured notes due 2042 are outstanding, Ameren Missouri will not permit a release date to occur, and so long as any of the 8.45% senior secured notes due 2039 are outstanding, Ameren Missouri will not optionally redeem, purchase, or otherwise retire in full the outstanding first mortgage bonds not subject to release provisions. (e)These bonds were issued by AMF. The bondholders of AMF have no recourse to Ameren Missouri’s assets. Ameren Missouri collects securitization surcharges to cover the principal and interest on the bonds as well as certain other qualified costs. The surcharges collected by Ameren Missouri on behalf of AMF are remitted to AMF and are not available to creditors of Ameren Missouri. Principal and interest payments on these bonds are payable semiannually on April 1 and October 1 of each year, which began on October 1, 2025, with final principal and interest payment due October 1, 2039. (f)These notes are collaterally secured by first mortgage bonds issued by Ameren Illinois under the Ameren Illinois mortgage indenture. The notes have a fall-away lien provision and will remain secured only as long as any first mortgage bonds issued under the Ameren Illinois mortgage indenture remain outstanding. Redemption, purchase, or maturity of all first mortgage bonds, including first mortgage bonds currently outstanding and any that may be issued in the future, would result in a release of the first mortgage bonds currently securing these notes, at which time these notes would become unsecured obligations. Considering the 2055 maturity date of the 5.625% first mortgage bonds, Ameren Illinois does not expect the first mortgage lien protection associated with these notes to fall away. (g)These bonds are first mortgage bonds issued by Ameren Illinois under the Ameren Illinois mortgage indenture. They are secured by substantially all Ameren Illinois property and franchises. (h)The following table presents the principal maturities schedule for the 2.45% senior unsecured notes due 2036:
Payment Date |  | Principal Payment
November 2029 | $ | 30
November 2036 |  | 45
Total | $ | 75
(i)The following table presents the principal maturities schedule for the 3.43% senior unsecured notes due 2050:
Payment Date |  | Principal Payment
August 2027 | $ | 50
August 2030 |  | 49
August 2032 |  | 50
August 2038 |  | 49
August 2043 |  | 77
August 2050 |  | 76
Total | $ | 351
(j)The following table presents the principal maturities schedule for the 2.96% senior unsecured notes due 2052:
Payment Date |  | Principal Payment
August 2040 | $ | 45
August 2052 |  | 50
Total | $ | 95
The following table presents the aggregate maturities of long-term debt, including current maturities, at December 31, 2025:
| Ameren (parent)(a) |  | Ameren Missouri(a) |  | Ameren Illinois(a) |  | ATXI(a) |  | Ameren Consolidated(a)
2026 | $ | 950 |  |  | $ | 23 |  |  | $ | — |  |  | $ | — |  |  | $ | 973 |
2027 | 500 |  |  | 424 |  |  | — |  |  | 50 |  |  | 974 |
2028 | 450 |  |  | 26 |  |  | 490 |  |  | — |  |  | 966 |
2029 | 700 |  |  | 477 |  |  | — |  |  | 30 |  |  | 1,207 |
2030 | — |  |  | 493 |  |  | 375 |  |  | 49 |  |  | 917 |
Thereafter | 1,550 |  |  | 6,864 |  |  | 5,448 |  |  | 532 |  |  | 14,394 |
Total | $ | 4,150 |  |  | $ | 8,307 |  |  | $ | 6,313 |  |  | $ | 661 |  |  | $ | 19,431 |
(a)Excludes unamortized discount, premium, and debt issuance costs of $19 million, $77 million, $54 million, and $2 million at Ameren (parent), Ameren Missouri, Ameren Illinois, and ATXI, respectively. In November and December 2024, Ameren (parent) purchased senior secured notes and first mortgage bonds issued by Ameren Missouri and first mortgage bonds issued by Ameren Illinois for $44 million in the aggregate. In June 2025, Ameren (parent) purchased senior secured notes and first mortgage bonds issued by Ameren Missouri and first mortgage bonds issued by Ameren Illinois for $24 million in the aggregate. On a consolidated basis, Ameren (parent)’s repurchase of these senior secured notes and first mortgage bonds were accounted for as a debt extinguishment and resulted in a pre-tax gain of $8 million and $16 million for the years ended December 31, 2025 and 2024, respectively, which is reflected in “Other Income, Net” on Ameren’s consolidated statement of income. Interest expense related to the repurchased bonds was $3 million and less than $1 million for the years ended December 31, 2025 and 2024, respectively. The following table presents Ameren Missouri’s and Ameren Illinois’ “Long-term Debt, Net - Related Parties” as of December 31, 2025 and 2024:
| 2025 |  | 2024
Ameren Missouri: |  |  |
3.65% Senior secured notes due 2045 | $ | 29 |  |  | $ | 7 |
4.00% First mortgage bonds due 2048 | 4 |  |  | — |
3.25% First mortgage bonds due 2049 | 33 |  |  | 33 |
2.625% First mortgage bonds due 2051 | 7 |  |  | 4 |
3.90% First mortgage bonds due 2052 | 15 |  |  | 14 |
Total long-term debt - related parties, gross | 88 |  |  | 58 |
Less: Unamortized debt issuance costs | (1) |  |  | (1) |
Long-term debt - related parties, net | $ | 87 |  |  | $ | 57 |
Ameren Illinois: |  |  |
3.70% First mortgage bonds due 2047 | $ | 1 |  |  | $ | 1 |
3.25% First mortgage bonds due 2050 | 2 |  |  | 2 |
2.90% First mortgage bonds due 2051 | 2 |  |  | — |
Long-term debt - related parties, net | $ | 5 |  |  | $ | 3 |
All classes of Ameren Missouri’s and Ameren Illinois’ preferred stock are entitled to cumulative dividends, have voting rights, and are not subject to mandatory redemption. The preferred stock of Ameren’s subsidiaries is included in “Noncontrolling Interests” on Ameren’s consolidated balance sheet. The following table presents the outstanding preferred stock of Ameren Missouri and Ameren Illinois, which is redeemable at the option of the issuer, at the prices shown below as of December 31, 2025 and 2024:
| Shares Outstanding |  | Redemption Price (per share) |  | 2025 |  | 2024
Ameren Missouri: |  |  |  |  |  |  |
Without par value and stated value of $100 per share, 25 million shares authorized |  |  |  |  |  |
$3.50 Series | 130,000 shares |  | $ | 110.00 |  |  | $ | 13 |  |  | $ | 13 |
$3.70 Series | 40,000 shares |  | 104.75 |  |  | 4 |  |  | 4 |
$4.00 Series | 150,000 shares |  | 105.625 |  |  | 15 |  |  | 15 |
$4.30 Series | 40,000 shares |  | 105.00 |  |  | 4 |  |  | 4 |
$4.50 Series | 213,595 shares |  | 110.00 |  | (a) | 21 |  |  | 21 |
$4.56 Series | 200,000 shares |  | 102.47 |  |  | 20 |  |  | 20 |
$4.75 Series | 20,000 shares |  | 102.176 |  |  | 2 |  |  | 2 |
$5.50 Series A | 14,000 shares |  | 110.00 |  |  | 1 |  |  | 1 |
Total |  | $ | 80 |  |  | $ | 80 |
Ameren Illinois: |  |  |  |  |  |  |
With par value of $100 per share, 2 million shares authorized |  |  |  |  |  |
4.00% Series | 144,275 shares |  | $ | 101.00 |  |  | $ | 14 |  |  | $ | 14 |
4.08% Series | 45,224 shares |  | 103.00 |  |  | 5 |  |  | 5 |
4.20% Series | 23,655 shares |  | 104.00 |  |  | 2 |  |  | 2 |
4.25% Series | 50,000 shares |  | 102.00 |  |  | 5 |  |  | 5 |
4.26% Series | 16,621 shares |  | 103.00 |  |  | 2 |  |  | 2 |
4.42% Series | 16,190 shares |  | 103.00 |  |  | 2 |  |  | 2 |
4.70% Series | 18,429 shares |  | 104.30 |  |  | 2 |  |  | 2 |
4.90% Series | 73,825 shares |  | 102.00 |  |  | 7 |  |  | 7 |
4.92% Series | 49,289 shares |  | 103.50 |  |  | 5 |  |  | 5 |
5.16% Series | 50,000 shares |  | 102.00 |  |  | 5 |  |  | 5 |
Total |  | $ | 49 |  |  | $ | 49 |
Total Ameren |  | $ | 129 |  |  | $ | 129 |
(a)In the event of voluntary liquidation, $105.50. Ameren has 100 million shares of $0.01 par value preferred stock authorized, with no such shares outstanding. Ameren Missouri has 7.5 million shares of $1 par value preference stock authorized, with no such shares outstanding. Ameren Illinois has 2.6 million shares of no par value preferred stock authorized, with no such shares outstanding. Ameren Under the DRPlus and its 401(k) plan, Ameren issued 0.4 million, 0.5 million, and 0.6 million shares of common stock in 2025, 2024, and 2023, respectively, received proceeds of $37 million, $33 million, and $39 million for the respective years, and had a receivable of $7 million and $7 million as of December 31, 2025 and 2024. In addition, Ameren issued 0.3 million, 0.2 million, and 0.5 million shares of common stock valued at $25 million, $16 million, and $40 million in 2025, 2024, 2023, respectively, for no cash consideration in connection with stock-based compensation. In May 2023, Ameren filed a Form S-3 registration statement with the SEC, authorizing the offering of 3 million additional shares of its common stock under the DRPlus, which expires in May 2026. Shares of common stock sold under the DRPlus are, at Ameren’s option, newly issued shares, treasury shares, or shares purchased in the open market or in privately negotiated contracts. In October 2023, Ameren, Ameren Missouri, and Ameren Illinois filed a Form S-3 shelf registration statement with the SEC, registering the issuance of an unspecified amount of certain types of securities. This registration statement expires in October 2026. In May 2022, Ameren filed a Form S-8 registration statement with the SEC, authorizing the offering of 7.5 million additional shares of its common stock under its 401(k) plan. Shares of common stock issuable under the 401(k) plan are, at Ameren’s option, newly issued shares, treasury shares, or shares purchased in the open market or in privately negotiated contracts. Ameren has entered into an equity distribution sales agreement pursuant to which Ameren may offer and sell from time to time its common stock through an ATM program, which includes the ability to enter into forward sale agreements. In August 2025, Ameren increased the amount of common stock available for sale under the ATM program by $1.25 billion to a total of $3 billion. Under the ATM, Ameren issued 5.8 million, 2.9 million, and 3.2 million shares of common stock and received proceeds of $530 million, $233 million, and $299 million in 2025, 2024 and 2023, respectively. These proceeds were net of $5 million, $2 million and $3 million, respectively, in compensation paid to selling agents. As of December 31, 2025, Ameren had approximately $1.5 billion of common stock remaining available for sale under the ATM program. In May 2025, Ameren entered into forward sale agreements separate from the ATM program with multiple counterparties relating to 6.4 million shares of common stock, with an initial forward sale price for the agreements of $91.89. The forward sale agreements can be settled at Ameren’s discretion on or prior to January 15, 2027. On a settlement date or dates, if Ameren elects to physically settle a forward sale agreement, Ameren will issue shares of common stock to the counterparties at the then-applicable forward sale price. Each initial forward sale price is subject to adjustment based on a floating interest rate factor equal to the overnight bank funding rate less a spread of 75 basis points, and will be subject to decrease on certain dates specified in the forward sale agreements by specified amounts related to expected dividends on shares of the common stock during the term of the forward sale agreements. If the overnight bank funding rate is less than or more than the spread on any day, the interest rate factor will result in a reduction or an increase, respectively, of the forward sale price. The forward sale agreements will be physically settled unless Ameren elects to settle in cash or to net share settle. At December 31, 2025, Ameren could have settled the forward sale agreements with physical delivery of 6.4 million shares of common stock to the respective counterparties in exchange for cash of $585 million. Alternatively, the forward sale agreements could have also been settled at December 31, 2025, with delivery of approximately $52 million of cash or approximately 0.5 million shares of common stock to the counterparties. In connection to the forward sale agreements, the various counterparties, or their affiliates, borrowed from third parties and sold 6.4 million shares of common stock. The gross sales price of these shares totaled $600 million. Ameren does not receive any proceeds from such sales of borrowed shares. The forward sale agreements have been classified as equity transactions. In February 2026, $350 million principal amount of Ameren (parent)’s 3.65% senior unsecured notes matured and was repaid with commercial paper borrowings. In March 2025, Ameren (parent) issued $750 million of 5.375% senior unsecured notes due March 2035, with interest payable semiannually on March 15 and September 15 of each year, beginning September 15, 2025. Net proceeds from this issuance were used for general corporate purposes, including the repayment of short-term debt. In September 2024, $450 million principal amount of Ameren (parent)’s 2.50% senior unsecured notes matured and was repaid with commercial paper borrowings. Ameren Missouri In April 2025, Ameren Missouri issued $500 million of 5.25% first mortgage bonds due April 2035, with interest payable semiannually on April 15 and October 15 of each year, beginning October 15, 2025. Net proceeds from this issuance were used to repay short-term debt. In January 2024, Ameren Missouri issued $350 million of 5.25% first mortgage bonds due January 2054, with interest payable semiannually on January 15 and July 15 of each year, beginning July 15, 2024. Net proceeds from this issuance were used for capital expenditures and to repay short-term debt. In April 2024, Ameren Missouri issued $500 million of 5.20% first mortgage bonds due April 2034, with interest payable semiannually on April 1 and October 1 of each year, beginning October 1, 2024. Net proceeds from this issuance were used for capital expenditures and to repay short-term debt. In April 2024, $350 million principal amount of Ameren Missouri’s 3.50% senior secured notes matured and was repaid with cash on hand. In October 2024, Ameren Missouri issued $450 million of 5.125% first mortgage bonds due March 2055, with interest payable semiannually on March 15 and September 15 of each year, beginning March 15, 2025. Net proceeds from this issuance were used for capital expenditures and to repay short-term debt. In December 2024, AMF issued $476 million of 4.85% securitized utility tariff bonds due October 2039, with principal and interest payable semiannually on April 1 and October 1 of each year, beginning October 1, 2025. Net proceeds from this issuance were used to finance energy transition costs related to the accelerated retirement of the Rush Island Energy Center, which included the remaining unrecovered net plant balance associated with the facility, among other costs, and to repay short-term debt. See Note 2 – Rate and Regulatory Matters for additional information on the securitization of Rush Island Energy Center costs. For information on Ameren Missouri’s capital contributions, refer to Capital Contributions in Note 13 – Related-party Transactions. Ameren Illinois In March and September 2025, Ameren Illinois issued $350 million and $350 million, respectively, of 5.625% first mortgage bonds due March 2055, with interest payable semiannually on March 1 and September 1 of each year, beginning September 1, 2025 and March 1, 2026, respectively. Net proceeds from the March 2025 issuance were used to repay $300 million principal amount of its 3.25% senior secured notes that matured in March 2025, and net proceeds of both issuances were used to repay a portion of its short-term debt. In June 2024, Ameren Illinois issued $625 million of 5.55% first mortgage bonds due July 2054, with interest payable semiannually on January 1 and July 1 of each year, beginning January 1, 2025. Net proceeds from this issuance were used to repay short-term debt. For information on Ameren Illinois’ capital contributions, refer to Capital Contributions in Note 13 – Related-party Transactions. ATXI In August 2024, ATXI issued $70 million of 5.17% senior unsecured notes due September 2039 and $70 million of 5.42% senior unsecured notes due September 2053, pursuant to an August 2024 note purchase agreement. Both series of senior unsecured notes have interest payable semiannually on March 1 and September 1 of each year, which began on March 1, 2025, and were issued through a private placement offering exempt from registration under the Securities Act of 1933, as amended. Net proceeds from these issuances were used to repay a $49 million principal payment of ATXI’s 3.43% senior unsecured notes at maturity and to repay short-term debt. Indenture Provisions and Other Covenants Ameren Missouri’s and Ameren Illinois’ indentures and articles of incorporation include covenants and provisions related to issuances of first mortgage bonds and preferred stock. Ameren Missouri and Ameren Illinois are required to meet certain ratios to issue additional first mortgage bonds and preferred stock. A failure to achieve these ratios would not result in a default under these covenants and provisions but would restrict the companies’ ability to issue bonds or preferred stock. The following table summarizes the required and actual interest coverage ratios for interest charges, dividend coverage ratios, and bonds and preferred stock issuable as of December 31, 2025, at an assumed interest rate of 7% and dividend rate of 8%.
| Required Interest Coverage Ratio(a) | Actual Interest Coverage Ratio | Bonds Issuable(b) |  | Required Dividend Coverage Ratio(c) | Actual Dividend Coverage Ratio | Preferred Stock Issuable |
Ameren Missouri | >2.0 | 3.2 | $3,777 |  | >2.5 | 219.0 | $3,702 |
Ameren Illinois | >2.0 | 6.6 | 9,482 |  | >1.5 | 3.6 | 203 | (d)
(a)Coverage required on the annual interest charges on first mortgage bonds outstanding and to be issued. Coverage is not required in certain cases when additional first mortgage bonds are issued on the basis of retired bonds. (b)Amount of bonds issuable based either on required coverage ratios or unfunded property additions, whichever is more restrictive. The amounts shown also include bonds issuable based on retired bond capacity of $895 million and $1,093 million at Ameren Missouri and Ameren Illinois, respectively. (c)Coverage required on the annual dividend on preferred stock outstanding and to be issued, as required in the respective company’s articles of incorporation. (d)Preferred stock issuable is restricted by the amount of preferred stock that is currently authorized by Ameren Illinois’ articles of incorporation. Ameren’s indenture does not require Ameren to comply with any quantitative financial covenants. The indenture does, however, include certain cross-default provisions. Specifically, either (1) the failure by Ameren to pay when due and upon expiration of any applicable grace period any portion of any Ameren indebtedness in excess of $25 million, or (2) the acceleration upon default of the maturity of any Ameren indebtedness in excess of $25 million under any indebtedness agreement, including borrowings under the Credit Agreements or the Ameren commercial paper program, constitutes a default under the indenture, unless such past due or accelerated debt is discharged or the acceleration is rescinded or annulled within a specified period. Ameren Missouri and Ameren Illinois and certain other nonregistrant Ameren subsidiaries are subject to Section 305(a) of the Federal Power Act, which makes it unlawful for any officer or director of a public utility, as defined in the Federal Power Act, to participate in the making or paying of any dividend from any funds “properly included in capital account.” The FERC has consistently interpreted the provision to allow dividends to be paid as long as (1) the source of the dividends is clearly disclosed, (2) the dividends are not excessive, and (3) there is no self-dealing on the part of corporate officials. At a minimum, Ameren believes that dividends can be paid by its subsidiaries that are public utilities from net income and retained earnings. In addition, under Illinois law, Ameren Illinois and ATXI may not pay any dividend on their respective stock unless, among other things, their respective earnings and earned surplus are sufficient to declare and pay a dividend after provisions are made for reasonable and proper reserves, or unless Ameren Illinois or ATXI has specific authorization from the ICC. Ameren Illinois’ articles of incorporation require dividend payments on its common stock to be based on ratios of common stock to total capitalization and other provisions related to certain operating expenses and accumulations of earned surplus. Ameren Illinois has made a commitment to the FERC to maintain a minimum 30% ratio of common stock equity to total capitalization. As of December 31, 2025, using the FERC-agreed upon calculation method, Ameren Illinois’ ratio of common stock equity to total capitalization was 55%. ATXI’s note purchase agreements includes financial covenants that require ATXI not to permit at any time (1) debt to exceed 70% of total capitalization or (2) secured debt to exceed 10% of total assets. At December 31, 2025, the Ameren Companies were in compliance with the provisions and covenants contained in their indentures and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreements. In order for the Ameren Companies to issue securities in the future, they will have to comply with all applicable requirements in effect at the time of any such issuances. Off-Balance-Sheet Arrangements At December 31, 2025, none of the Ameren Companies had any material off-balance-sheet financing arrangements, other than their investments in variable interest entities, letters of credit, and the forward sale agreements relating to common stock. See Note 1 – Summary of Significant Accounting Policies for further detail concerning variable interest entities.

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