The average councillor is white, male and more than 20 years older than the typical citizen, with their age topping 60 for the first time.
A census of councillors produced by the LGA shows 67% of councillors are male, 96% are white and 44% are aged 65 or over. However, there are significant variations between political parties and regions.
The data contrasts sharply with Office for National Statistics figures for the population as a whole, which is 89% white, with only 17% aged 65 or over.
The census, which was undertaken in September and October last year and published last month, shows the average age of a councillor tops 60 for the first time in recent memory, reaching 60.2. This is up from 59.7 in 2010 and 57.8 in 2004, the years when previous censuses were undertaken.
Labour councillors were more representative of the population in terms of gender, age and ethnicity than those of other parties. Nine per cent of its councillors are from a non-white background, compared with just 1.5% of Conservatives and 2.3% of Liberal Democrats.
The party also had the highest proportion of female councillors at 37%, and the highest proportion aged under 65.
The smaller parties were at the extremes in terms of gender representation, with 89% of Ukip councillors being male, compared with 60% for those belonging to the Green party.
Councillors in the south-west are the oldest in England, with an average age of 62.3 while their London counterparts are the youngest, aged 56.5 on average.
The research, undertaken by the National Foundation for Educational Research, also reveals Conservative councillors would be more likely than their counterparts in other parties to be able to carry on their role without the financial benefits available to members. Over a quarter (28.6%) of Tories said they could carry on without
the current benefits, compared with 18.1% of Labour councillors and 22.6% of Liberal Democrats.
The findings, which also show there has been little change in how far councillors represent their communities in terms of gender, age, ethnic origin, disability status and caring responsibilities over the past decade, have raised alarm.
“The point of representatives is they should be representative,” Jessica Crowe, executive director of the Centre for Public Scrutiny, told LGC.
Ms Crowe, a member of the 2007 independent Councillors Commission, which investigated the barriers and incentives to becoming a councillor, urged councils to consider working more flexibly and changing meeting times to attract a more diverse range of members.
Anthony Zacharzewski, founder of the Democratic Society, said: “No one expects councillors exactly to match their wards, but the lack of progress is disappointing.
“Councils must open up opportunities to be a councillor by making sure the role is possible with young children or a full-time job.”
Simon Henig (Lab), leader of Durham CC and chair
of the Association of Labour Councillors, said: “If people are going to give up earnings [to be a councillor], not only are they weakening their salary but their pension too, which is why it’s so unfortunate councillors have been barred from the local government pension scheme.”