Telephone Code in Bihar vary from district to district. And since Bihar is a vast state, there are many districts and hence too many telephone codes. If you want to communicate to any one in Bihar, you need to know the telephone code of that particular place because dialing of the telephone code is mandatory before dialing the actual telephone number.
Given below is the list of telephone code of some important cities and districts of Bihar :
| Area | Telephone Code |
| ADHAURA | 6180 |
| AMARPUR | 6420 |
| ARARIA | 6453 |
| ARERAJ | 6258 |
| ARRAH | 6182 |
| ARWAL | 6337 |
| AURANGABAD | 6186 |
| BAGAHA | 6251 |
| BANKA | 6424 |
| BANMANKHI | 6467 |
| BARACHAKIA | 6257 |
| BARAUNI | 6279 |
| BARH | 6132 |
| BAROSI | 6451 |
| BEGUSARAI | 6243 |
| BENIPATTI | 6271 |
| BENIPUR | 6242 |
| BETTIAH | 6254 |
| BHABHUA | 6189 |
| BHAGALPUR | 641 |
| BIDUPUR | 6229 |
| BIHARSHARIF | 6112 |
| BIKRAM | 6135 |
| BIKRAMGANJ | 6185 |
| BIRPUR | 6471 |
| BUXER | 6183 |
| CHAKAI | 6347 |
| CHAPARA | 6152 |
| DALSINGHSARAI | 6278 |
| DANAPUR | 6115 |
| DARBHANGA | 6272 |
| DAUDNAGAR | 6328 |
| DHAKA | 6250 |
| DHAMDAHA | 6462 |
| DUMRAON | 6323 |
| EKMA | 6155 |
| FORBESGANJ | 6455 |
| GAYA | 631 |
| GOGRI | 6245 |
| GOPALGANJ | 6156 |
| H.KHARAGPUR | 6342 |
| HAJIPUR | 6224 |
| HATHUA | 6150 |
| HILSA | 6111 |
| IMAMGANJ | 6331 |
| JAHANABAD | 6114 |
| JAINAGAR | 6246 |
| JAMUI | 6345 |
| JHAJHA | 6349 |
| JHANJHARPUR | 6273 |
| KAHALGAON | 6429 |
| KATIHAR | 6452 |
| KATORIA | 6425 |
| KHAGARIA | 6244 |
| KISHANGANJ | 6466 |
| KORHA | 6457 |
| LAKHISARAI | 6346 |
| MADHEPURA | 6476 |
| MADHUBANI | 6276 |
| MAHARAJGANJ | 6153 |
| MAHUA | 6227 |
| MAIRWA | 6157 |
| MALLEHPUR | 6348 |
| MASRAKH | 6159 |
| MOHANIA | 6187 |
| MONGHYR | 6344 |
| MOTIHARI | 6252 |
| MOTIPUR | 6223 |
| MUZAFFARPUR | 621 |
| NABINAGAR | 6332 |
| NARKATIAGANJ | 6253 |
| NAUGACHIA | 6421 |
| NAWADA | 6324 |
| PAKRIBARWAN | 6325 |
| PAKRIDAYAL | 6259 |
| PATNA | 612 |
| PHULPARAS | 6277 |
| PIRO | 6181 |
| PUPRI | 6228 |
| PURENA | 6454 |
| RAFIGANJ | 6327 |
| RAJAULI | 6336 |
| RAMNAGAR | 6256 |
| RANIGANJ | 6461 |
| RAXAUL | 6255 |
| ROHTAS | 6188 |
| ROSERA | 6275 |
| S.BAKHTIARPUR | 6475 |
| SAHARSA | 6478 |
| SAMASTIPUR | 6274 |
| SASARAM | 6184 |
| SEIKHPURA | 6341 |
| SHEOHAR | 6222 |
| SHERGHATI | 6326 |
| SIDHAWALIA | 6151 |
| SINGHWARA | 6247 |
| SITAMARHI | 6226 |
| SIWAN | 6154 |
| SONEPUR | 6158 |
| THAKURGANJ | 6459 |
| WAZIRGANJ | 6322 |
