Local Calling Guide

Area code/prefix search

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NPA: 281 [Rate centres in NPA 281] [Dial plan for NPA 281]

NXX: 623

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
281-623 A Humble TX HSTNTX01G04  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560      
281-623 0 Humble TX   515J IP HORIZON LLC 560   2017-12-31   
281-623 1 Humble TX   903C ONVOY, LLC - TX 560   2018-02-24   
281-623 2 Humble TX   5562 METROPCS, INC. 560   2017-12-31   
281-623 3 Humble TX   5562 METROPCS, INC. 560   2017-12-31   
281-623 4 Humble TX   903C ONVOY, LLC - TX 560   2018-04-14   
281-623 5 Humble TX   318J COMCAST IP PHONE, LLC 560   2018-05-30   
281-623 6 Humble TX   5562 METROPCS, INC. 560   2018-04-03   
281-623 7 Humble TX   5562 METROPCS, INC. 560   2018-04-03   
281-623 8 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2018-04-21   
281-623 9 Humble TX   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 560   2017-12-30   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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