San Fernando comprises 24 barangays with an estimated population of 81,148. 23 of its barangays (96%) are connectivity dead zones with no recorded cell tower from either the national registry or crowdsourced data.
| Barangay | Population | Towers | Coverage |
|---|---|---|---|
| Bonacao | 1,654 | 0 | Dead zone: no towers from any source |
| Bulalang | 1,230 | 0 | Dead zone: no towers from any source |
| Cabuling | 2,483 | 0 | Dead zone: no towers from any source |
| Candelaria | 3,133 | 0 | Dead zone: no towers from any source |
| Cayaga | 1,165 | 0 | Dead zone: no towers from any source |
| Dao | 1,568 | 0 | Dead zone: no towers from any source |
| Durian | 2,622 | 0 | Dead zone: no towers from any source |
| Halapitan (Pob.) | 11,683 | 1 | Crowdsourced signal only (no registered tower) |
| Iglugsad | 1,627 | 0 | Dead zone: no towers from any source |
| Kalagangan | 8,641 | 0 | Dead zone: no towers from any source |
| Kawayan | 3,299 | 0 | Dead zone: no towers from any source |
| Kibongcog | 4,396 | 0 | Dead zone: no towers from any source |
| Little Baguio | 6,323 | 0 | Dead zone: no towers from any source |
| Mabuhay | 2,364 | 0 | Dead zone: no towers from any source |
| Magkalungay | 7,659 | 0 | Dead zone: no towers from any source |
| Malayanan | 3,789 | 0 | Dead zone: no towers from any source |
| Matupe | 1,831 | 0 | Dead zone: no towers from any source |
| Nacabuklad | 3,655 | 0 | Dead zone: no towers from any source |
| Namnam | 4,770 | 0 | Dead zone: no towers from any source |
| Palacpacan | 339 | 0 | Dead zone: no towers from any source |
| Sacramento Valley | 2,018 | 0 | Dead zone: no towers from any source |
| San Jose | 1,932 | 0 | Dead zone: no towers from any source |
| Santo Domingo | 1,818 | 0 | Dead zone: no towers from any source |
| Tugop | 1,149 | 0 | Dead zone: no towers from any source |