According to Electoral Commissioner Patilias Gamato, the total eligible voting population was 55, 000 but only 21, 000 casted their votes.
From the figures, more than half of the voting population did not vote.
Timothy Masiu, who was declared the winner in front of 11 other candidates on July 4, 2016, collected 8, 323 votes.
The election writs were returned to Governor-General Sir Michael Ogio last Thursday morning, and he was sworn into office by Parliament Speaker Theo Zurenouc a few hours later.
Masiu said many people did not turn up to vote because they thought with a year before the national election, the by-election was a waste of time.
He added that another reason was because people do not trust politicians anymore because of many empty promises.
But he thanked his people for their trust and confidence in voting him.
Caption: The return of writs for South Bougainville Open by-election on Thursday.