| District | Count of Postal Codes |
|---|---|
| Araria | 171 |
| Arwal | 82 |
| Aurangabad | 277 |
| Banka | 221 |
| Begusarai | 239 |
| Bhagalpur | 254 |
| Bhojpur | 303 |
| Buxar | 186 |
| Darbhanga | 368 |
| Gaya | 379 |
| Gopalganj | 208 |
| Jamui | 165 |
| Jehanabad | 126 |
| Kaimur (Bhabua) | 133 |
| Katihar | 185 |
| Khagaria | 154 |
| Kishanganj | 91 |
| Lakhisarai | 91 |
| Madhepura | 202 |
| Madhubani | 427 |
| Munger | 115 |
| Muzaffarpur | 419 |
| Nalanda | 327 |
| Nawada | 189 |
| Pashchim Champaran | 274 |
| Patna | 438 |
| Purbi Champaran | 424 |
| Purnia | 178 |
| Rohtas | 270 |
| Saharsa | 166 |
| Samastipur | 378 |
| Saran | 389 |
| Sheikhpura | 100 |
| Sheohar | 46 |
| Sitamarhi | 301 |
| Siwan | 329 |
| Supaul | 211 |
| Vaishali | 297 |
| Araria |
| Arwal |
| Aurangabad |
| Banka |
| Begusarai |
| Bhagalpur |
| Bhojpur |
| Buxar |
| Darbhanga |
| Gaya |
| Gopalganj |
| Jamui |
| Jehanabad |
| Kaimur (Bhabua) |
| Katihar |