Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 804 [Rate centres in NPA 804] [Dial plan for NPA 804]

NXX: 574

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
804-574 A Rockville VA RCMDVAITXKX  4644 TELEPORT COMMUNICATIONS AMERICA, LLC - VA 248      
804-574 0 Rockville VA   515J IP HORIZON LLC 248   2021-08-13   
804-574 1 Rockville VA   515J IP HORIZON LLC 248   2024-02-10   
804-574 2 Rockville VA   515J IP HORIZON LLC 248   2024-12-29   
804-574 3 Rockville VA   624H ONVOY SPECTRUM, LLC 248   2021-12-02   
804-574 4 Rockville VA   624H ONVOY SPECTRUM, LLC 248   2021-12-02   
804-574 5 Rockville VA   624H ONVOY SPECTRUM, LLC 248   2021-06-01   
804-574 6 Rockville VA   4644 TELEPORT COMMUNICATIONS AMERICA, LLC - VA 248   2021-05-31   
804-574 7 Rockville VA   318J COMCAST IP PHONE, LLC 248   2023-06-04   
804-574 8 Rockville VA   515J IP HORIZON LLC 248   2024-02-10   
804-574 9 Rockville VA   515J IP HORIZON LLC 248   2024-12-29   

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

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