The Municipality of San Emilio, Ilocos Sur is geographically located along the Cordillera Ranges particularly in the northern part. Nine (9) Upland Local Governments surround San Emilio: on the north lies the Province of Abra; on the northeast, the Municipality of Villaviciosa (Province of Abra); on the east the Municipalities of Tubo and Luba (Province of Abra); on the southeast the Municipality of Quirino (Ilocos Sur); on the south lies the Municipality of Gregorio del Pilar (Ilocos Sur); and on the southwest the City of Candon (Ilocos Sur) and on the west the Municipalities of Lidlidda and Burgos (Ilocos Sur). It bears a distorted pear shape, and consist of eight highly elevated barangays:
Cabaoan (Poblacion), Kalumsing, Lancuas, Matibuey, Paltoc, Sibsibbu, San Miliano and Tiagan. It is approximately 17 kilometers east of the national highway at the Santiago junction (Curba), near the boundary of the Municipality of Santiago and the City of Candon. The main access road is through the newly paved and concreted Santiago-Banayoyo-Lidlidda-San Emilio National Highway. It is accessible with any type of transportation or vehicles. Several rivers cascade through the municipality, the most prominent of which is the Abra River on the eastern most section of the municipality, providing abundant water supply for irrigation to the adjacent barangays. In general, however, water supply for the whole municipality is insufficient, except when the rains come and fill the creeks and rivers in the rainy season.
