Marinduque has 218 barangays across 6 municipalities. 192 barangays (88%) are connectivity dead zones.
| Municipality | Barangays | Dead zones |
|---|---|---|
| Boac (Capital) | 61 | 49 (80%) |
| Buenavista | 15 | 13 (87%) |
| Gasan | 25 | 24 (96%) |
| Mogpog | 37 | 30 (81%) |
| Santa Cruz | 55 | 54 (98%) |
| Torrijos | 25 | 22 (88%) |