Section 117Omnibus Election Code of the Philippines (Batas Pambansa Blg. 881), Sec. 117

Qualifications of a voter. - Every citizen of the Philippines, not otherwise disqualified by law, eighteen years of age or over, who shall have resided in the Philippines for one year and in the city or municipality wherein he proposes to vote for at least six months immediately preceding the election, may be registered as a voter.

Any person who transfers residence to another city, municipality or country solely by reason of his occupation; profession; employment in private or public service; educational activities; work in military or naval reservations; service in the army, navy or air force; the constabulary or national police force; or confinement or detention in government institutions in accordance with law, shall be deemed not to have lost his original residence.