Chelmsford City Council in Essex, England is elected every four years. Since the last boundary changes in 2003 the council has comprised 57 councillors elected from 24 wards.
A by-election occurs when seats become vacant between council elections. Below is a summary of by-elections from 1983 onwards. Full by-election results are listed under the last regular election preceeding the by-election and can be found by clicking on the ward name.