[5] The mayor serves as chairman of the council, and is responsible for allocating department assignments to his fellow commissioners.

His post is largely honorific; most powers exercised by mayors in cities of Portland's size are vested in the council as a whole.

However, the mayor does have some powers, such as declaring an emergency and acting as police commissioner.

Although, beginning with the 2025 mayoral term, Portland will switch to a Council-Mayor form of government.

(2010-2017) Note: The color shown in the number (#) column denotes registered political party (red for Republican, blue for Democratic, teal for the People's Party (Populist), gray for Independent).

As of February 2024, only two mayors are missing from the collection; William H. Farrar (1862–1863), and Hamilton Boyd (1868–1869).