Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 557 [Rate centres in NPA 557] [Dial plan for NPA 557]

NXX: 240

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-240 A Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 0 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 1 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 2 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 3 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 4 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 5 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 6 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 7 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 8 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   
557-240 9 Ladue MO   7218 TELEPORT COMMUNICATIONS AMERICA, LLC - MO 520   2025-10-27   

Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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