Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 640 [Rate centres in NPA 640] [Dial plan for NPA 640]

NXX: 275

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
640-275 A Lawrenceville NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 222   2025-06-20   
640-275 7 Lawrenceville NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 222   2025-06-20   
640-275 8 Lawrenceville NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 222   2025-06-20   
640-275 9 Lawrenceville NJ   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 222   2025-06-20   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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