| | | | | | STD Numbers of Bihar | |
| | Bihar Areas | STD Codes | Imamganj | 06331 | Jahanabad | 06114 | Jainagar | 06246 | Jamui | 06345 | Jhajha | 06349 | Jhanjharpur | 06273 | Kahalgaon | 06429 | Katihar | 06452 | Katoria | 06425 | Khagaria | 06244 | Kishanganj | 06466 | Korha | 06457 | Lakhisarai | 06346 | Madhepura | 06476 | Madhubani | 06276 | Maharajganj | 06153 | Mahua | 06227 | Mairwa | 06157 | Mallehpur | 06348 | Masrakh | 06159 | Mohania | 06187 | Monghyr | 06344 |
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