Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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OCN: 321J HD CARRIER LLC

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NPA-NXX BLOCK Rate Centre Region Switch LATA LIR Eff date Disc date
303-303 4 Denver CO DNVRCOMA32Z  656   2024-10-27   
303-303 5 Denver CO DNVRCOMA32Z  656   2024-10-27   
303-303 6 Denver CO DNVRCOMA32Z  656   2024-10-27   
303-303 7 Denver CO DNVRCOMA32Z  656   2024-10-27   
303-303 8 Denver CO DNVRCOMA32Z  656   2024-10-27   
303-303 9 Denver CO DNVRCOMA32Z  656   2024-10-27   
304-307 9 Madison WV CHTNWVLE2MD  254   2020-11-01   
304-915 1 Charleston Zone 7 WV CHTNWVLE2MD  254   2020-11-02   
304-915 9 Charleston Zone 7 WV CHTNWVLE2MD  254   2020-11-02   
307-292 A Cheyenne WY CHYNWYRF8MD  654      
307-292 7 Cheyenne WY CHYNWYRF8MD  654   2020-11-02   
307-292 8 Cheyenne WY CHYNWYRF8MD  654   2020-11-02   
307-292 9 Cheyenne WY CHYNWYRF8MD  654   2020-08-08   
307-302 8 Cody WY CHYNWYRF8MD  654   2020-10-18   
307-449 7 Rock Springs WY   654   2025-11-21   
307-449 8 Rock Springs WY   654   2025-11-21   
307-474 5 Cody WY   654   2025-11-21   
307-474 6 Cody WY   654   2025-11-21   
307-522 2 Rock Springs WY CHYNWYRF8MD  654   2020-09-27   
309-802 A Peoria IL PEORILPJXXZ  368      
309-802 9 Peoria IL PEORILPJXXZ  368   2020-10-09   
309-880 A Ipava IL PEORILPJ01Z  368      
309-880 9 Ipava IL PEORILPJ01Z  368   2021-07-10   
309-920 A Bloomington IL BLTNILTSCMD  366      
309-920 8 Bloomington IL BLTNILTSCMD  366   2023-05-11   
309-920 9 Bloomington IL BLTNILTSCMD  366   2023-05-11   
312-473 9 Chicago Zone 01-Calumet IL   358   2025-10-11   
312-879 1 Chicago Zone 01-Canal IL   358   2025-10-11   
313-547 A Detroit Zone 5 MI SFLDMIMKDMD  340      
313-547 9 Detroit Zone 5 MI SFLDMIMKDMD  340   2021-07-24   
313-552 A Detroit Zone 1 MI SFLDMIMKCMD  340      
313-552 9 Detroit Zone 1 MI SFLDMIMKCMD  340   2020-11-21   
313-620 2 Detroit Zone 3 MI   340   2025-11-03   
313-732 3 Detroit Zone 2 MI   340   2025-11-03   
313-857 2 Detroit Zone 6 MI   340   2025-11-03   
314-278 1 Kirkwood MO   520   2026-02-23   
314-278 2 Kirkwood MO   520   2026-02-23   
314-806 A St Louis MO STLSMOGZJMD  520      
314-806 9 St Louis MO STLSMOGZJMD  520   2020-11-21   
315-484 1 Syracuse NY   136   2026-01-18   
315-885 2 Syracuse NY   136   2026-02-09   
316-368 A Wichita KS WCHTKSTPWMD  532      
316-368 9 Wichita KS WCHTKSTPWMD  532   2020-09-25   
318-522 A Shreveport LA SHPTLAMA30Z  486      
318-522 8 Shreveport LA SHPTLAMA30Z  486   2023-05-11   
318-522 9 Shreveport LA SHPTLAMA30Z  486   2023-05-11   
318-735 7 Shreveport LA   486   2025-08-15   
318-735 8 Shreveport LA   486   2025-08-15   
319-379 A Iowa City IA IWCYIA708MD  635      
319-379 8 Iowa City IA IWCYIA708MD  635   2020-11-20   

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Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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