Nearly 62 million Filipinos will head to the polls on Monday in a vote that is expected to strengthen President Rodrigo Duterte’s grip on power.
Voting began at 2200 GMT Sunday and will close at 18:00.
Duterte, who completed half of his six-year term, is not contesting himself, but several of his children are.
His daughter Sara is running to keep her post as mayor in Davao city, while sons Sebastian is seeking the city's vice-mayoral seat and Paolo standing for a seat in the lower House of Representatives.
The elections are seen by some as a referendum on the president, that could allow him to expand his contentious anti-drug crackdown.
The results for municipal and city mayors and councils are expected late Monday, with winners for the Senate and congressional seats likely to be out on Friday.