Siyambalape Postal Code
| City | Postal Code | District |
|---|---|---|
| Heiyanthuduwa | 11618 | Gampaha |
| Gonawala | 11630 | Gampaha |
| Makola | 11640 | Gampaha |
| Biyagama | 11650 | Gampaha |
| Malwana | 11670 | Gampaha |
| Biyagama EPZ | 11672 | Gampaha |
| Dompe | 11680 | Gampaha |
| Dekatana | 11690 | Gampaha |
| Demalagama | 11692 | Gampaha |
| Delgoda | 11700 | Gampaha |
| Weliveriya | 11710 | Gampaha |
| Henegama | 11715 | Gampaha |
| Buthpitiya | 11720 | Gampaha |
| Wathurugama | 11724 | Gampaha |
| Radawana | 11725 | Gampaha |