He said he was alarmed the subjects of the mayor's polling were not revealed.
In a response to Mr Brewer, the council said: "Auckland Council invests in market and social research to ensure decision-makers can have confidence in the validity and legitimacy of the information they use to make decisions," adding that the work met the standards of professional and academic research bodies.
The figures do not include surveys and polls commissioned by council-controlled organisations, which Mr Brewer believed would add millions of dollars.
He said ratepayers should be concerned that staff time was recently spent surveying councillors and local board members on what they think of each other and the organisation.
"The council always hides behind the statutory need to consult for the likes of the Annual Plan, but let's not forget the Government amended the Local Government Act to ensure public consultation is now much less arduous," he said. "However despite less annual documentation and consultation legally required, the costs keep going up."
Poll spending
• $9.3 million over four years
• Includes $310,000 spending on people's panel
• Plus $253,206 spending by mayoral office