Belfast City Council is the local authority with responsibility for part of Belfast, the largest city of Northern Ireland. The council serves an estimated population of 348,005 (mid-2022 est.), the largest of any district council in Northern Ireland, while being the smallest by area. Belfast City Council is the primary council of the Belfast Metropolitan Area, a grouping of six former district councils with commuter towns and overspill from Belfast, containing a total population of 579,276.

Belfast is the capital city and principal port of Northern Ireland, standing on the banks of the River Lagan and connected to the open sea through Belfast Lough and the North Channel. It is second to Dublin as the largest city on the island of Ireland with a population in 2021 of 345,418 and a metro area population of 671,559.