San Fabian comprises 34 barangays with an estimated population of 93,855. 11 of its barangays (32%) are connectivity dead zones with no recorded cell tower from either the national registry or crowdsourced data.
| Barangay | Population | Towers | Coverage |
|---|---|---|---|
| Alacan | 2,341 | 0 | Dead zone: no towers from any source |
| Ambalangan-Dalin | 5,886 | 14 | Crowdsourced signal only (no registered tower) |
| Angio | 5,135 | 3 | Crowdsourced signal only (no registered tower) |
| Anonang | 6,189 | 1 | Crowdsourced signal only (no registered tower) |
| Aramal | 3,498 | 0 | Dead zone: no towers from any source |
| Bigbiga | 655 | 0 | Dead zone: no towers from any source |
| Binday | 2,825 | 2 | Crowdsourced signal only (no registered tower) |
| Bolaoen | 1,688 | 1 | Crowdsourced signal only (no registered tower) |
| Bolasi | 3,534 | 2 | Crowdsourced signal only (no registered tower) |
| Cabaruan | 646 | 3 | Crowdsourced signal only (no registered tower) |
| Cayanga | 3,228 | 8 | Crowdsourced signal only (no registered tower) |
| Colisao | 1,767 | 0 | Dead zone: no towers from any source |
| Gumot | 1,099 | 0 | Dead zone: no towers from any source |
| Inmalog | 3,515 | 4 | Crowdsourced signal only (no registered tower) |
| Inmalog Norte | 2,254 | 1 | Crowdsourced signal only (no registered tower) |
| Lekep-Butao | 1,079 | 0 | Dead zone: no towers from any source |
| Lipit-Tomeeng | 2,837 | 3 | Crowdsourced signal only (no registered tower) |
| Longos | 3,169 | 5 | Crowdsourced signal only (no registered tower) |
| Longos Proper | 1,510 | 1 | Crowdsourced signal only (no registered tower) |
| Longos-Amangonan-Parac-Parac Fabrica | 3,841 | 2 | Crowdsourced signal only (no registered tower) |
| Mabilao | 2,332 | 1 | Crowdsourced signal only (no registered tower) |
| Nibaliw Central | 887 | 0 | Dead zone: no towers from any source |
| Nibaliw East | 1,881 | 0 | Dead zone: no towers from any source |
| Nibaliw Magliba | 1,389 | 3 | Crowdsourced signal only (no registered tower) |
| Nibaliw Narvarte (Nibaliw West Compound) | 3,709 | 0 | Dead zone: no towers from any source |
| Nibaliw Vidal (Nibaliw West Proper) | 4,667 | 1 | Crowdsourced signal only (no registered tower) |
| Palapad | 2,053 | 1 | Crowdsourced signal only (no registered tower) |
| Poblacion | 3,051 | 1 | Crowdsourced signal only (no registered tower) |
| Rabon | 1,285 | 0 | Dead zone: no towers from any source |
| Sagud-Bahley | 3,952 | 2 | Crowdsourced signal only (no registered tower) |
| Sobol | 4,372 | 0 | Dead zone: no towers from any source |
| Tempra-Guilig | 3,146 | 1 | Crowdsourced signal only (no registered tower) |
| Tiblong | 2,083 | 1 | Crowdsourced signal only (no registered tower) |
| Tocok | 2,352 | 5 | Crowdsourced signal only (no registered tower) |