Council consideration of the proposition would happen "if and when progress has been made on the concept" and the Government had given a clear signal.
A Family Centre report said the $18.40 figure was based on the cost of Otago University's "basic" food diet for a couple with two children ($226 a week), the national lower-quartile rent for a three-bedroom house of $275 a week, and other costs totalling $537 a week based on the average spending by families earning below the median household income.
The living wage campaign has gained further traction with backing by 126 union, community and religious groups.
Human resources manager Danny Harrison said the council employed 296 staff and of that number, 24 permanent staff and 26 casual staff were paid less than $18.40 per hour.
"Casual staff work on an 'as and when' basis and their rate will depend on the individual job they are undertaking," Mr Harrison said.
"In addition there are 28 rural fire officers but some of these include permanent council staff who are already included in the figure of 296 staff. All rural fire officers are paid more than the 'living wage'," he said.
"The council employs two individuals as contractors and, in addition, a number of companies are contracted to provide services on a tender basis, for example Opus and Veolia. "We do not have control over their staff conditions and pay," Mr Harrison said.
The council's annual salary/wage budget for 2012/2013 is $14.1 million.
Meanwhile, Auckland and Wellington councils have agreed to investigate the feasibility of adopting the living wage.
Wellington Mayor Celia Wade-Brown said she "would very much like to move towards a living wage".
But any changes would be gradual, subject to a feasibility study and after consulting ratepayers.
Auckland Mayor Len Brown said his council would consider a report by Lower Hutt's Anglican Family Centre calculating the wage required for a couple with two children to "live with dignity and to participate as active citizens in society".
Labour leader David Shearer supports the campaign and said it would allow a lift in the incomes of New Zealanders to better support their families.
Mr Shearer said the Labour Party would champion the living wage alongside community groups "to do what we can to support the movement".
Initial Auckland Council figures show it would cost $2.5 million a year to raise the wages of 1544 people paid under $18.40 an hour as direct employees of the council and all except two other council-controlled organisations.
Business New Zealand chief executive Phil O'Reilly said the organisation welcomed the study into wages and living conditions, yet implored the bigger condition be looked at instead of just wages.
Subsidising transport and childcare for low-wage workers were avenues businesses could use to support their employees without hiking up wages, he said.
The living wage concept was fraught as living costs differed region to region and with individuals' circumstances.
Mr O'Reilly said it was more important to up-skill workers so that they could progress up through the labour market. "To just say it's about wages is not correct."
Green Party co-leader Metiria Turei said the party supported the concept and believed central and local government and profitable employers should be the first to sign up. She conceded the wage rise could not happen overnight.
The Public Service Association - which represents 58,000 workers - estimated about 16 per cent of its members, mainly women, were not earning a living wage.
