Santa Monica (Sapao) comprises 11 barangays with an estimated population of 11,520. 10 of its barangays (91%) are connectivity dead zones with no recorded cell tower from either the national registry or crowdsourced data.
| Barangay | Population | Towers | Coverage |
|---|---|---|---|
| Abad Santos | 599 | 0 | Dead zone: no towers from any source |
| Alegria | 404 | 0 | Dead zone: no towers from any source |
| Bailan | 3,073 | 0 | Dead zone: no towers from any source |
| Garcia | 713 | 0 | Dead zone: no towers from any source |
| Libertad | 1,167 | 0 | Dead zone: no towers from any source |
| Mabini | 786 | 0 | Dead zone: no towers from any source |
| Mabuhay (Pob.) | 1,752 | 0 | Dead zone: no towers from any source |
| Magsaysay | 424 | 0 | Dead zone: no towers from any source |
| Rizal | 1,346 | 0 | Dead zone: no towers from any source |
| T. Arlan (Pob.) | 547 | 2 | Crowdsourced signal only (no registered tower) |
| Tangbo | 709 | 0 | Dead zone: no towers from any source |