You may decide to complain about your local council because:
a council service has not been properly delivered
there have been long delays in addressing an issue
council staff are rude or communication is poor
the council has failed to fulfil legal obligations
In order to lodge a formal complaint, the first step is to complain to the council service provider (via the complaints department of your local council). If an initial complaint is not resolved, it may be possible to escalate the complaint to the council's complaints officer (also via the complaints department of your local council).
If the complaints department or complaints officer of a local council fails to satisfactorily resolve a complaint, it can then be escalated to the Local Government and Social Care Ombudsman (in England and Wales) or the Scottish Public Services Ombudsman (in Scotland).
For housing related complaints, rather than pursuing a complaint, it may be more effective to ask for a decision to be reviewed - eg in the case of:
See the Shelter website for more information on housing complaints.