| # | Village / Locality | Post Office | PIN Code | Sub District | Type |
|---|---|---|---|---|---|
| 301 | Basantpur Diara | Ramnagar BO | 📍 841504 | Raghunathpur | Branch Post Office |
| 302 | Basaon | Basaowan BO | 📍 841406 | Basantpur | Branch Post Office |
| 303 | Basarh | Raghunathpur SO Siwan | 📍 841504 | Raghunathpur | Post Office - PO |
| 304 | Basauli | Nandamura BO | 📍 841203 | Lakri Nabiganj | Branch Post Office |
| 305 | Basawanbari | Barhria SO | 📍 841232 | Barharia | Post Office - PO |
| 306 | Basawanbari | Madhopur BO | 📍 841232 | Barharia | Branch Post Office |
| 307 | Basdewa | Jagdishpur Kothi BO | 📍 841243 | Nautan | Branch Post Office |
| 308 | Bashant nagar | Sahuli BO | 📍 841286 | Hasanpura | Branch Post Office |
| 309 | Bashantpur | Titra BO | 📍 841245 | Ziradei | Branch Post Office |
| 310 | Bashantpur | Khujhwa SO | 📍 841502 | Raghunathpur | Post Office - PO |
| 311 | Bashilpur | Sarauti BO | 📍 841241 | Pachrukhi | Branch Post Office |
| 312 | Basirpur | Goreakothi SO | 📍 841434 | Goriakothi | Post Office - PO |
| 313 | Basuapur | Gauri BO | 📍 841234 | Darauli | Branch Post Office |
| 314 | Basuhari | Balaun BO | 📍 841244 | Guthani | Branch Post Office |
| 315 | Batrauli | Amlori BO | 📍 841226 | Siwan | Branch Post Office |
| 316 | Bauna | Tariwani BO | 📍 841235 | Darauli | Branch Post Office |
| 317 | Bauri | Belauri BO | 📍 841239 | Guthani | Branch Post Office |
| 318 | Bawan Dih | Chainpur BO | 📍 841439 | Siswan | Branch Post Office |
| 319 | Bazari Tola | Sahuli BO | 📍 841286 | Hasanpura | Branch Post Office |
| 320 | Bazidpur | Khawaspur BO | 📍 841416 | Lakri Nabiganj | Branch Post Office |
| 321 | Bazidpur | Sikandrpur BO | 📍 841434 | Goriakothi | Branch Post Office |
| 322 | Bedauli | Barkamanjha BO | 📍 841243 | Mairwa | Branch Post Office |
| 323 | Bedauli | Sahpur SO | 📍 841243 | Mairwa | Post Office - PO |
| 324 | Bela | Pakwalia BO | 📍 841238 | Daraundha | Branch Post Office |
| 325 | Belahi | Kherai BO | 📍 841231 | Andar | Branch Post Office |
| 326 | BeLahi | Bhwrajpur BO | 📍 841231 | Andar | Post Office - PO |
| 327 | belahi Tola | Jaijore BO | 📍 841231 | Andar | Branch Post Office |
| 328 | Belaon | Belaon BO | 📍 841235 | Darauli | Branch Post Office |
| 329 | Belaspur | Bilaspur BO | 📍 841239 | Mairwa | Branch Post Office |
| 330 | Belaur | Belaur BO | 📍 841239 | Guthani | Branch Post Office |
| 331 | Belaura Dih | Raghunathpur SO Siwan | 📍 841504 | Raghunathpur | Post Office - PO |
| 332 | Belauri | Belauri BO | 📍 841239 | Guthani | Branch Post Office |
| 333 | Beldari tola | Bhikha Bandh Satjora BO | 📍 841244 | Daraundha | Branch Post Office |
| 334 | Belsan Yadav Tola | Belsand BO | 📍 841413 | Barharia | Branch Post Office |
| 335 | Belsand Primary School | Belsand BO | 📍 841413 | Barharia | Branch Post Office |
| 336 | Belsand Tola | Belsand BO | 📍 841413 | Barharia | Branch Post Office |
| 337 | Belsui | Krishnapali BO | 📍 841234 | Darauli | Branch Post Office |
| 338 | beluhi tola | Jaijore BO | 📍 841231 | Andar | Branch Post Office |
| 339 | Belwar | Raghunathpur SO Siwan | 📍 841504 | Raghunathpur | Post Office - PO |
| 340 | Belwasa | Hussainganj SO | 📍 841237 | Ziradei | Post Office - PO |
| 341 | Bengali Bharauli | K.T.Bharouli BO | 📍 841404 | Daraundha | Post Office - PO |
| 342 | Bensuar | Benusar BO | 📍 841227 | Siwan | Branch Post Office |
| 343 | Benusar | Benusar Bujurg BO | 📍 841227 | Siwan | Branch Post Office |
| 344 | Benusar Buzurg | Benusar Bujurg BO | 📍 841227 | Pachrukhi | Branch Post Office |
| 345 | Berhea | Dhanuti BO | 📍 841226 | Ziradei | Branch Post Office |
| 346 | Bhabhopali | Rachhopali BO | 📍 841427 | Barharia | Branch Post Office |
| 347 | Bhada Kalan | Gaushalaroad Siwan SO | 📍 841227 | Siwan | Post Office - PO |
| 348 | Bhada Khurd | Gaushalaroad Siwan SO | 📍 841227 | Siwan | Post Office - PO |
| 349 | Bhada Khurd | Nabiganj BO | 📍 841407 | Lakri Nabiganj | Post Office - PO |
| 350 | Bhadaur | Bangra BO | 📍 841203 | Siswan | Branch Post Office |