Two thirds of councillors are male, revealing the extent of sexism faced by women in local government, according to a new report.
Research by the Fawcett Society also showed that nine out of 10 council leaders are men.
The campaign group said the study revealed sexism was a problem across all levels of politics.
Head of policy Daisy Sands said: “We have found numerous examples, across the country and from a range of parties, of male councillors making sexist, offensive and derogatory remarks about both women generally and their female colleagues.
“These incidents should be considered in light of the male dominance of local government. More than two thirds of local elected representatives are men, and the higher up the tree you go the fewer women there are.
“In fact, over the past 10 years the number of women running town halls has actually decreased.
“It seems clear that sexism of the kind we found is putting women off local politics.
This is bad for our democracy, and means very important decisions are being made with few women around the table.
“Local government accounts for almost a quarter of all public spending in the UK but how and where this money is spent is being decided in town halls where an average seven in 10 councillors are male.
“We know also that spending cuts at this level are having a skewed impact on services women rely on – research has shown that local authorities have in recent years cut funding for services offering support to victims of domestic violence and sexual abuse by almost a third.”
Fawcett urged all political parties to tackle the under representation of women in politics as a matter of urgency.