| Post office | Karsar B.O |
| Pin code | 841504 |
| Office type | B.O |
| Taluk / city | Siwan |
| District name | Siwan |
| State name | Bihar |
| Delivery status | Delivery |
| Division name | Siwan |
| Region name | Muzaffarpur |
| Circle name | Bihar |
| Related sub office | Raghunathpur S.O (Siwan) |
| Related head office | Siwan H.O |
| Pincode | Post office name | City | District | State |
|---|---|---|---|---|
| 841504 | Admapur B.O | Siwan | Siwan | Bihar |
| 841504 | Harnathpur B.O | Siwan | Siwan | Bihar |
| 841504 | Karsar B.O | Siwan | Siwan | Bihar |
| 841504 | Narhan B.O | Siwan | Siwan | Bihar |
| 841504 | Raghunathpur S.O (Siwan) | Siwan | Siwan | Bihar |
| 841504 | Rajpur B.O | Siwan | Siwan | Bihar |
| 841504 | Ramnagar B.O | Siwan | Siwan | Bihar |