| Office Name | S.S.Factory B.O |
| Pincodes | 841226 |
| Area | S.S.Factory |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sadarpur B.O |
| Pincodes | 841232 |
| Area | Sadarpur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sadiha B.O |
| Pincodes | 841507 |
| Area | Sadiha |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Safiabad B.O |
| Pincodes | 841416 |
| Area | Safiabad |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sahatwar B.O |
| Pincodes | 841439 |
| Area | Sahatwar |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sahlaur B.O |
| Pincodes | 841227 |
| Area | Sahlaur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sahpur S.O |
| Pincodes | 841243 |
| Area | Sahpur |
| Office Status | Sub Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | 06157-111111 |
| Office Name | Sahrkola B.O |
| Pincodes | 841406 |
| Area | Sahrkola |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sahsrawan B.O |
| Pincodes | 841408 |
| Area | Sahsrawan |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sahuli B.O |
| Pincodes | 841286 |
| Area | Sahuli |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Saidpura B.O |
| Pincodes | 841439 |
| Area | Saidpura |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sani Basantpur B.O |
| Pincodes | 841439 |
| Area | Sani Basantpur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sanjalpur B.O |
| Pincodes | 841245 |
| Area | Sanjalpur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Santhi B.O |
| Pincodes | 841502 |
| Area | Santhi |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sarari B.O |
| Pincodes | 841434 |
| Area | Sarari |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sarauti B.O |
| Pincodes | 841241 |
| Area | Sarauti |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Saraya Sah Mohamd B.O |
| Pincodes | 841506 |
| Area | Saraya Sah Mohamd |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sareyarampur B.O |
| Pincodes | 841234 |
| Area | Sareyarampur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sarhrwa B.O |
| Pincodes | 841239 |
| Area | Sarhrwa |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |
| Office Name | Sarif Jalalpur B.O |
| Pincodes | 841416 |
| Area | Sarif Jalalpur |
| Office Status | Branch Post Office |
| Postal Circle | Bihar |
| Postal Division | Siwan |
| Postal Region | Muzaffarpur |
| District | Siwan |
| State | Bihar |
| Telephone No. | Na |