Lidlidda, officially the Municipality of Lidlidda, is a municipality located in Ilocos Sur province in the Ilocos region of the Philippines. According to the 2024 census, the municipality has a population of 4,846 people.
As a municipality in Ilocos Sur, Lidlidda is part of the broader Ilocos region, which encompasses the northwestern coastal area of Luzon. The municipality operates under the standard administrative structure of Philippine municipalities, governed by local officials and integrated into the provincial system of Ilocos Sur.