In 1918 the borough was divided into North and South constituencies.
Previously the borough was divided into 26 wards and 6 areas, used for elections from 1978 to 1998.
The borough is divided into 20 wards, with 48 councillors.
The borough is divided into four districts located in three different neighborhoods.
The borough is divided into three electoral areas which between them return 16 members.
The former borough was divided into six different districts before the 2009 reorganization.
The borough is divided into eighty one neighborhoods called colonias.
For local elections the borough is divided into 15 wards, and three of them cover Portland.
The borough is divided into 23 wards, each returning from one to three councillors.
The borough is divided into 21 wards, each with 3 councillors.