Punters dropped more than $10.2 million into Wanganui pokie machines last year - about $28,000 each day.
Figures from the Department of Internal Affairs reveal gambling machine expenditure decreased slightly in the city during the 12 months to December, down $156,458 from 2011.
The number of pokie machines also dipped slightly, down five since 2011 to 257.
Delyse Nelson, Nga Tai O Te Awa gambling awareness health promoter, said while the reduced figures were encouraging, pokie machines continued to cause huge problems in the city.
"Pokie machines are designed to be addictive, there is no limit to the amount of money one can feed a pokie machine, they are easily accessible with some venues being located in our high-deprivation areas."
Those who suffered from problem gambling often fell into financial hardship and could also suffer from depression, anxiety, suicidal thoughts and behaviour, 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.
Thirty-seven per cent of gaming machine proceeds must be returned to the community, according to the Gambling Act.
The number of gaming machines declined, 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 ... indicates that people are starting to understand about pokie machines and how addictive and dangerous they are," spokeswoman Andree Froude said.
Ms Froude said about 40 per cent of money dropped into pokies was spent by people who had a gambling problem.
The Problem Gambling Foundation has warned that proposed changes to the Gambling Act, which would enable pub and bar owners to take the profit on pokie machines if implemented, would result in an increase in problem gambling. APNZ