The council agrees it is wrong – describing the practice as 'disgraceful' – but says the government forces it to sell the data.
Andrew Jay, chairman of the association, said, "When completing my electoral registration form I was amazed to learn that the council is in the practice of selling the list of names of persons on the Electoral Register to private companies for profit.
"Not only is it a gross invasion of privacy but results in each household receiving a substantial amount of unsolicited mail, with consequent damage to the environment."
The cabinet member responsible, Cllr Troy Tester, said, "I would certainly agree that it is disgraceful that local councils are required by law to sell the edited version of the electoral register."
He said a recent survey by the Local Government Association found that most councils were opposed to the practice along with the great majority of electoral registration staff, all of whom were concerned that it might discourage people to register.
"I would encourage everyone to tick the box on their electoral registration form to ensure their name doesn't appear on the edited register and doesn't get bought for commercial purposes," he said
"I would also agree with the government's own Information Commissioner, Richard Thomas, who last year said in a report to the Ministry of Justice, 'We feel that selling the edited register is an unsatisfactory way for local authorities to treat personal information.'
"I can only hope that this or some future government will listen and take these concerns seriously and act to stop this practice."
Last year the sale of personal data brought in £1,431. Almost all of this related to sales to credit agencies. A council spokesperson said that, as far as they were aware, there were no sales for commercial purposes.