A paltry rise of 25 cents an hour in the minimum wage wouldn't even buy struggling families a block of cheese, the Whangarei Child Poverty Action Group said.
The group said government was out of touch with reality and often came up with the argument that a substantial wage increase would close down businesses.
''How many are on minimum wage but not working 40 hours a week?,'' group spokeswoman Sherry Carne asked.
Labour Minister Simon Bridges last month announced the minimum wage would rise from $13.50 an hour to $13.75.
The training and new entrants' minimum wages will increase from $10.80 to $11, which is 80 per cent of the adult minimum wage.
Ms Carne said once taxes were deducted, low-paid workers would have very little left from the new minimum wage rate to provide for their families.
She said lack of housing and high rates of rheumatic fever in Northland were a direct result of insufficient income.
Asked about the government's argument that raising minimum wage to $18.40 -as advocated by the Living Wage Campaign - would result in workers losing their jobs, she replied: ''There's so many people that haven't got jobs.
''The government can't expect people to be paid a pittance and expect the society and NGOs to provide kids with breakfast and lunch,'' Ms Carne said
While there was a push to get people off benefits, she questioned how they would survive on $13.75 if they were not working 40 hours a week.
Mr Bridges said the new minimum rate was a careful balance between protecting workers and ensuring jobs were not lost.