Ilocos Norte has 559 barangays across 23 municipalities. 281 barangays (50%) are connectivity dead zones.
| Municipality | Barangays | Dead zones |
|---|---|---|
| Adams | 1 | 1 (100%) |
| Bacarra | 43 | 17 (40%) |
| Badoc | 31 | 14 (45%) |
| Bangui | 14 | 8 (57%) |
| Banna (Espiritu) | 20 | 17 (85%) |
| Burgos | 11 | 4 (36%) |
| Carasi | 3 | 2 (67%) |
| City of Batac | 43 | 27 (63%) |
| Currimao | 23 | 12 (52%) |
| Dingras | 31 | 18 (58%) |
| Dumalneg | 4 | 4 (100%) |
| Laoag City (Capital) | 80 | 9 (11%) |
| Marcos | 13 | 13 (100%) |
| Nueva Era | 11 | 11 (100%) |
| Pagudpud | 16 | 6 (38%) |
| Paoay | 31 | 16 (52%) |
| Pasuquin | 33 | 14 (42%) |
| Piddig | 23 | 13 (57%) |
| Pinili | 25 | 18 (72%) |
| San Nicolas | 24 | 6 (25%) |
| Sarrat | 24 | 12 (50%) |
| Solsona | 22 | 15 (68%) |
| Vintar | 33 | 24 (73%) |