San Isidro comprises 12 barangays with an estimated population of 7,636. 12 of its barangays (100%) are connectivity dead zones with no recorded cell tower from either the national registry or crowdsourced data.
| Barangay | Population | Towers | Coverage |
|---|---|---|---|
| Buhing Calipay | 525 | 0 | Dead zone: no towers from any source |
| Del Carmen (Pob.) | 792 | 0 | Dead zone: no towers from any source |
| Del Pilar | 246 | 0 | Dead zone: no towers from any source |
| Macapagal | 250 | 0 | Dead zone: no towers from any source |
| Pacifico | 1,140 | 0 | Dead zone: no towers from any source |
| Pelaez | 726 | 0 | Dead zone: no towers from any source |
| Roxas | 634 | 0 | Dead zone: no towers from any source |
| San Miguel | 1,424 | 0 | Dead zone: no towers from any source |
| Santa Paz | 127 | 0 | Dead zone: no towers from any source |
| Santo Niño | 460 | 0 | Dead zone: no towers from any source |
| Tambacan | 245 | 0 | Dead zone: no towers from any source |
| Tigasao | 1,067 | 0 | Dead zone: no towers from any source |