$AMT · American Tower Corporation

American Tower Corporation filed a preliminary prospectus supplement dated September 9, 2026, to offer three series of senior unsecured notes: Senior Notes due 2031, Senior Notes due 2033, and Senior Notes due 2036. The document is subject to completion, and the principal amounts, interest rates, offering prices, and related figures were not yet specified. Interest would be paid in cash semiannually on March 15 and September 15, beginning March 15, 2027. The notes would mature on September 15 of their respective years.

The notes would rank equally with American Tower’s other senior unsecured debt and would be structurally subordinated to the obligations of its subsidiaries. The company may redeem the notes at any time in whole or in part for cash at the redemption prices described in the supplement. The notes would not be listed on any securities exchange, and there is currently no public market for them. J.P. Morgan, BofA Securities, Citigroup, Morgan Stanley, and Scotiabank are listed as joint book-running managers. The filing also directs investors to the risk factors in the supplement and in American Tower’s 2025 Annual Report.