All postcodes in SS1 9
| Postcode | Place | Type |
|---|---|---|
| SS1 9SY | Southend-on-Sea | large user |
| SS1 9SZ | Southend-on-Sea | large user |
| SS1 9TW | Southend-on-Sea | large user |
| SS1 9UA | Southend-on-Sea | large user |
| SS1 9UP | Southend-on-Sea | large user |
| SS1 9US | Southend-on-Sea | large user |
| SS1 9WB | Southend-on-Sea | large user |
| SS1 9WE | Southend-on-Sea | large user |
| SS1 9WF | Southend-on-Sea | large user |
| SS1 9WQ | Southend-on-Sea | large user |
| SS1 9WS | Southend-on-Sea | large user |
| SS1 9XD | Southend-on-Sea | large user |
| SS1 9XE | Southend-on-Sea | large user |
| SS1 9XN | Southend-on-Sea | large user |
| SS1 9YG | Southend-on-Sea | large user |
| SS1 9YU | Southend-on-Sea | large user |
| SS1 9ZY | — | large user |
| SS1 9ZZ | — | large user |