Gasan comprises 25 barangays with an estimated population of 26,469. 24 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 |
|---|---|---|---|
| Antipolo | 1,079 | 0 | Dead zone: no towers from any source |
| Bachao Ibaba | 762 | 0 | Dead zone: no towers from any source |
| Bachao Ilaya | 849 | 0 | Dead zone: no towers from any source |
| Bacongbacong | 451 | 0 | Dead zone: no towers from any source |
| Bahi | 1,509 | 1 | Crowdsourced signal only (no registered tower) |
| Bangbang | 1,333 | 0 | Dead zone: no towers from any source |
| Banot | 796 | 0 | Dead zone: no towers from any source |
| Banuyo | 866 | 0 | Dead zone: no towers from any source |
| Barangay I (Pob.) | 456 | 0 | Dead zone: no towers from any source |
| Barangay II (Pob.) | 230 | 0 | Dead zone: no towers from any source |
| Barangay III (Pob.) | 378 | 0 | Dead zone: no towers from any source |
| Bognuyan | 378 | 0 | Dead zone: no towers from any source |
| Cabugao | 799 | 0 | Dead zone: no towers from any source |
| Dawis | 2,224 | 0 | Dead zone: no towers from any source |
| Dili | 1,067 | 0 | Dead zone: no towers from any source |
| Libtangin | 998 | 0 | Dead zone: no towers from any source |
| Mahunig | 933 | 0 | Dead zone: no towers from any source |
| Mangiliol | 356 | 0 | Dead zone: no towers from any source |
| Masiga | 1,448 | 0 | Dead zone: no towers from any source |
| Matandang Gasan | 1,259 | 0 | Dead zone: no towers from any source |
| Pangi | 1,476 | 0 | Dead zone: no towers from any source |
| Pinggan | 1,811 | 0 | Dead zone: no towers from any source |
| Tabionan | 1,160 | 0 | Dead zone: no towers from any source |
| Tapuyan | 1,611 | 0 | Dead zone: no towers from any source |
| Tiguion | 2,240 | 0 | Dead zone: no towers from any source |