Executive Brief

  • Alliant Energy Corporation priced a $725 million public offering of 5.750% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2056 (the “Notes”) on September 23, 2025 (Item 8.01).
  • The Notes will be issued under an Indenture dated September 26, 2025, with The Bank of New York Mellon Trust Company, N.A. as trustee (Item 8.01).
  • The offering is registered under an automatic shelf registration statement on Form S-3 filed December 15, 2023, amended September 22, 2025, with a prospectus supplement filed September 25, 2025 (Item 8.01).
  • Underwriters include BofA Securities, MUFG Securities Americas, Barclays Capital, Goldman Sachs & Co. LLC, and J.P. Morgan Securities LLC (Item 8.01).
  • Legal opinions on the Notes’ legality and U.S. federal income tax considerations were issued by Perkins Coie LLP dated September 26, 2025 (Item 8.01).
  • Exhibits filed include the Underwriting Agreement, Indenture, Supplemental Indenture, legal opinions, consents, and the press release announcing pricing (Item 9.01).
  • This filing primarily serves to file exhibits related to the Notes offering and incorporates them by reference into the Registration Statement (Item 8.01).
  • No financial guidance, operational impacts, or governance changes disclosed.
  • No material risks or uncertainties beyond standard offering terms explicitly stated.
  • Next steps include issuance of Notes under the Indenture on or after September 26, 2025.

Item-by-Item Analysis

Item 8.01 – Other Events

  • What happened: Alliant Energy Corporation entered into an Underwriting Agreement on September 23, 2025, to sell $725 million aggregate principal amount of 5.750% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2056 in a public offering.
  • Parties/terms:
    • Underwriters: BofA Securities, Inc., MUFG Securities Americas Inc., Barclays Capital Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC.
    • Notes: 5.750% fixed interest rate, junior subordinated, reset rate feature, maturity in 2056.
    • Indenture dated September 26, 2025, with The Bank of New York Mellon Trust Company, N.A. as trustee.
    • Notes issued under a First Supplemental Indenture dated September 26, 2025.
    • Registered under automatic shelf registration statement (Form S-3 No. 333-276062) filed December 15, 2023, amended September 22, 2025.
    • Prospectus supplement filed September 25, 2025, sets forth terms of the Notes.
  • Conditions/closing: Notes to be issued under Indenture on or after September 26, 2025.
  • Legal opinions: Perkins Coie LLP issued opinions on legality and tax considerations dated September 26, 2025.
  • New information: This is new information regarding the pricing and execution of the Notes offering.
  • Source: (Item 8.01, paras 1-10), (Exhibits 1.1, 4.1, 4.2, 5.1, 8.1, 99.1).

Item 9.01 – Financial Statements and Exhibits

  • Exhibits filed:
    • 1.1 Underwriting Agreement dated September 23, 2025.
    • 4.1 Indenture dated September 26, 2025.
    • 4.2 First Supplemental Indenture dated September 26, 2025.
    • 5.1 Legal opinion of Perkins Coie LLP on Notes legality.
    • 8.1 Tax opinion of Perkins Coie LLP.
    • 23.1 and 23.2 Consents of Perkins Coie LLP.
    • 99.1 Press release dated September 23, 2025, announcing pricing.
    • 104 Inline XBRL cover page.
  • Source: (Item 9.01, para d).

Exhibits Summary

  • Exhibit 1.1: Underwriting Agreement with detailed terms of the offering and underwriting syndicate.
  • Exhibit 4.1 & 4.2: Indenture and Supplemental Indenture defining the Notes’ terms, trustee role, and reset rate mechanics.
  • Exhibit 5.1 & 8.1: Legal and tax opinions confirming compliance and tax treatment.
  • Exhibit 99.1: Press release announcing pricing of the $725 million Notes at 5.750% due 2056.
  • No additional financial or operational details beyond offering terms.

Financial & Dilution Impact

  • Debt issuance of $725 million fixed-to-fixed reset rate junior subordinated notes.
  • Interest rate fixed at 5.750%.
  • Maturity in 2056, implying long-term debt increase.
  • No mention of use of proceeds or impact on leverage ratios.
  • No equity dilution as this is a debt offering.

Timeline & Required Actions

  • Indenture and Supplemental Indenture dated September 26, 2025.
  • Notes issuance expected on or shortly after September 26, 2025.
  • No shareholder approvals or other conditions disclosed.
  • Registration Statement and Prospectus Supplement already filed.

Risks & Monitoring

  • No explicit new risk factors disclosed.
  • Standard risks related to junior subordinated debt and reset rate features apply.
  • Monitor interest rate reset terms and potential impact on future interest expense.
  • No material adverse change or termination rights disclosed.

Investor Takeaways

  • The offering increases Alliant Energy’s long-term debt by $725 million at a fixed 5.750% coupon.
  • The junior subordinated nature may affect debt seniority and credit metrics.
  • The reset rate feature introduces interest rate risk at reset dates.
  • No immediate operational or governance changes.
  • Investors should monitor future filings for use of proceeds and impact on credit profile.

Metadata & Quality Checks

  • No OCR or formatting issues detected.
  • Non-GAAP reconciliation: Not applicable.
  • Forward-looking statements: Not explicitly stated.
  • Related-party transactions: None disclosed.

Final Checklist

  • Identified all disclosed Items: Only Item 8.01 and 9.01 present.
  • Extracted concrete facts with dates, amounts, parties.
  • Summarized exhibits and incremental info.
  • Quantified financial impact.
  • Noted timeline and next steps.
  • Highlighted risks and investor takeaways.
  • Verified metadata and quality.

Summary

Alliant Energy Corporation priced a $725 million offering of 5.750% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2056, with closing expected September 26, 2025. The offering is registered under an existing shelf registration, with legal and tax opinions filed. This increases long-term debt with no equity dilution. Investors should monitor the impact of the reset rate feature and future disclosures on use of proceeds and credit metrics.

Original Filing