Bagac comprises 14 barangays with an estimated population of 27,533. 3 of its barangays (21%) are connectivity dead zones with no recorded cell tower from either the national registry or crowdsourced data.
| Barangay | Population | Towers | Coverage |
|---|---|---|---|
| Atilano L. Ricardo | 2,758 | 11 | Crowdsourced signal only (no registered tower) |
| Bagumbayan (Pob.) | 1,243 | 2 | Crowdsourced signal only (no registered tower) |
| Banawang | 5,570 | 17 | Crowdsourced signal only (no registered tower) |
| Binuangan | 286 | 0 | Dead zone: no towers from any source |
| Binukawan | 1,447 | 10 | Crowdsourced signal only (no registered tower) |
| Ibaba | 897 | 9 | Crowdsourced signal only (no registered tower) |
| Ibis | 961 | 1 | Crowdsourced signal only (no registered tower) |
| Pag-asa (Wawa-Sibacan) | 4,528 | 5 | Crowdsourced signal only (no registered tower) |
| Parang | 2,493 | 2 | Crowdsourced signal only (no registered tower) |
| Paysawan | 471 | 0 | Dead zone: no towers from any source |
| Quinawan | 883 | 0 | Dead zone: no towers from any source |
| San Antonio | 1,238 | 2 | Crowdsourced signal only (no registered tower) |
| Saysain | 3,164 | 2 | Crowdsourced signal only (no registered tower) |
| Tabing-Ilog (Pob.) | 1,594 | 2 | Crowdsourced signal only (no registered tower) |