Punters dropped nearly $31.5 million into Northland pokie machines last year - about $86,000 each day.
Figures from the Department of Internal Affairs revealed gaming machine expenditure fell in the 12 months to December by about $595,500, while the number of pokie machines dipped slightly to 2748.
Addiction services provider Nga Manga Puriri Trust said Northland's large number of pokie machines put young people at risk.
"Gambling addiction already exists within youth culture,'' trust spokeswoman Leyla Lyndon-Tonga said.
We want to see sinking-lid policies that will help reduce the enormous social cost of problem gambling. Andree Froude, Problem Gambling Foundation spokeswoman "Their computer literacy is a lot more advanced than it was say 10 years ago, which places them at a higher risk given that pokie machines are electronic machines."
The prevalence of machines in the Far North was a major issue, Mrs Lyndon-Tonga said.
Figures showed there were 343 gaming machines in the Far North last year, compared to 71 in Kaipara and 343 in Whangarei.
"The Far North has high deprivation, high poverty and the highest number of pokie machines [in Northland]. This places young people in those areas at an even higher risk of developing gambling addictions," she said.
Nationally, Kiwis spent nearly $840 million on pokie machines last year - $27.1 million (3.1 per cent) less than the previous year.
The number of gaming machines declined nationally, from 18,133 to 17,670. There were also 29 fewer gaming machine venues compared with 2011.
The Problem Gambling Foundation said the figures were encouraging.
"It certainly indicates that people are starting to understand about pokie machines and how addictive and dangerous they are," spokeswoman Andree Froude said.
"We want to see sinking-lid policies in place in our communities and that will help reduce the harm and enormous social cost and impact of problem gambling."
Thirty-seven per cent of gaming machine proceeds must be returned to the community, according to the Gambling Act.
Ms Froude said about 40 per cent of money dropped into pokies was spent by people who had a gambling problem and many punters who lost money could not afford it.
Research also showed pokie machines were concentrated in poorer areas.
The Problem Gambling Foundation has warned that proposed changes to the Gambling Act, which would enable bar owners to take profit on pokie machines, if implemented, would result in an increase in problem gambling.