Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 623

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-623 A Moline IL RCISILRIX4X  506J TWILIO INTERNATIONAL, INC. 634      
309-623 0 Moline IL   6529 T-MOBILE USA, INC. 634   2024-02-21   
309-623 1 Moline IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 634   2021-08-20   
309-623 2 Moline IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 634   2024-01-29   
309-623 3 Moline IL   506J TWILIO INTERNATIONAL, INC. 634   2021-08-04   
309-623 4 Moline IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 634      
309-623 5 Moline IL   224C ONVOY, LLC 634   2021-04-05   
309-623 6 Moline IL   224C ONVOY, LLC 634   2021-04-05   
309-623 7 Moline IL   508J CENTURYLINK COMMUNICATIONS, LLC 634   2016-10-13   
309-623 8 Moline IL   224C ONVOY, LLC 634   2021-04-05   
309-623 9 Moline IL   224C ONVOY, LLC 634   2021-04-05   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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