Service is open to all consumers (active or inactive) of San Nicolas Water District (SANIWAD) in the following Barangay service area:
| 1. | Poblacion East | 11. | Sta. Maria West | 21. | San Isidro |
| 2. | Poblacion West | 12. | Sta. Maria East | 22. | Bensican |
| 3. | Casaratan | 13. | Cacabugaoan | 23. | Dalumpinas |
| 4. | Nagkaysa | 14. | Lungao | 24. | Salingcob |
| 5. | San Roque | 15. | Sto. Tomas | 25. | Salpad |
| 6. | Siblot (Tramo) | 16. | Malilion | 26. | San Rafael East |
| 7. | San Jose | 17. | Camindoroan | 27. | San Rafael Centro |
| 8. | Nining | 18. | Camanggaan | 28. | San Rafael West |
| 9. | Cabitnongan | 19. | Cabuloan | 29. | San Felipe East |
| 10. | Calaocan | 20. | Calanutian | 30. | San Felipe West |