The six-month job will set up former city Managing Director Roy Amemiya for benefits he can access for the rest of his life.
Rick Blangiardi was sworn in Saturday as the chief executive officer of the City and County of Honolulu.
Honolulu will have five new City Council members on Jan. 2.
The council chair cited family reasons for his decision to step down, effective Sept. 23, just a few months before his final term ends.
The diverse pool of candidates includes those with backgrounds in management, education, government, construction and activism.
Voters in District 5 will choose from a recent community activist, a seasoned political veteran or a longtime legislative staffer.
Former state Rep. Andria Tupola has a huge financial advantage over a trio of first-time council candidates running to disrupt politics-as-usual in District 1.
A council meeting improperly included a last-minute resolution about the use of Honolulu police resources during the Mauna Kea protests.