Omnibus Election Code
Section 13. Regular election for President and Vice-President. - The regular election for President and Vice-President of the Philippines shall be held on the first Monday of May Nineteen hundred eighty seven (1987) and on the same day every six years thereafter. The President-elect and the Vice-President-elect shall assume office at twelve o'clock noon on the thirtieth day of June next following the election and shall end at noon of the same date, six years thereafter when the term of his successor shall begin.