Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 773 [Rate centres in NPA 773] [Dial plan for NPA 773]

NXX: 903

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
773-903 A Chicago Zone 06-Kedzie IL   224C ONVOY, LLC 358   2025-10-05   
773-903 0 Chicago Zone 06-Kedzie IL   224C ONVOY, LLC 358   2025-10-05   
773-903 1 Chicago Zone 06-Kedzie IL   224C ONVOY, LLC 358   2025-10-05   
773-903 2 Chicago Zone 06-Kedzie IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2025-10-06   
773-903 3 Chicago Zone 06-Kedzie IL   321J HD CARRIER LLC 358   2025-10-10   
773-903 6 Chicago Zone 06-Kedzie IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2025-10-06   
773-903 8 Chicago Zone 06-Kedzie IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2025-10-06   

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

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