Population by Grama Niladhari division
| GN Division | Total population |
| Sainthamaruthu 01 | 2182 |
| Sainthamaruthu 02 | 2311 |
| Sainthamaruthu 03 | 2946 |
| Sainthamaruthu 04 | 1662 |
| Sainthamaruthu 05 | 1320 |
| Sainthamaruthu 06 | 1213 |
| Sainthamaruthu 07 | 1740 |
| Sainthamaruthu 081 | 1508 |
| Sainthamaruthu 09 | 2724 |
| Sainthamaruthu 10 | 1731 |
| Sainthamaruthu 11 | 1890 |
| Sainthamaruthu 12 | 1877 |
| Sainthamaruthu 13 | 1208 |
| Sainthamaruthu 14 | 1456 |
| Sainthamaruthu 15 | 2198 |
| Sainthamaruthu 16 | 2249 |
| Sainthamaruthu 17 | 1878 |
| Total | 32093 |
Population by Gender
| GN Division | Male | Female | Total Population |
| Sainthamaruthu 01 | 1079 | 1103 | 2182 |
| Sainthamaruthu 02 | 1139 | 1172 | 2311 |
| Sainthamaruthu 03 | 1498 | 1448 | 2946 |
| Sainthamaruthu 04 | 850 | 812 | 1662 |
| Sainthamaruthu 05 | 652 | 668 | 1320 |
| Sainthamaruthu 06 | 593 | 620 | 1213 |
| Sainthamaruthu 07 | 887 | 853 | 1740 |
| Sainthamaruthu 08 | 762 | 746 | 1508 |
| Sainthamaruthu 09 | 1347 | 1377 | 2724 |
| Sainthamaruthu 10 | 855 | 876 | 1731 |
| Sainthamaruthu 11 | 946 | 941 | 1890 |
| Sainthamaruthu 12 | 938 | 939 | 1877 |
| Sainthamaruthu 13 | 626 | 582 | 1208 |
| Sainthamaruthu 14 | 724 | 732 | 1456 |
| Sainthamaruthu 15 | 1121 | 1077 | 2198 |
| Sainthamaruthu 16 | 1151 | 1098 | 2249 |
| Sainthamaruthu 17 | 963 | 915 | 1878 |
| Total | 16134 | 15959 | 32093 |
