Commission on Elections (COMELEC) Chairman Andres Bautista is leaving the poll body at the end of this year.
In a press conference at noon, Bautista said he sent a letter of resignation to President Rodrigo Duterte and it is effective on December 31, 2017.
He cited personal reasons for his move.
"Hindi kaila sa inyo ang mga hamon sa aking personal na buhay (it is not unknown to you the challenges in my personal life)," he said.
He refused to discuss his rift with his estranged wife Patricia, who had accused him of having amassed ill-gotten wealth.
"Ito ang tamang panahon para ipahayag ang aking pagre-resign (this is the right time to announce my resignation)," the poll chairman said.
He said Congress is expected to approve anytime today COMELEC's budget for next year.
The preparations for the barangay and Sangguniang Kabataan elections will also begin in January next year.
Bautista said he wants to have a smooth transition at the COMELEC when he leaves.
This is why he wants the President to have ample time to find his replacement.