Government considered scrapping the duty-free allowance altogether, but has decided to cut it to 50 cigarettes, 50g of loose tobacco or 50g of cigars, beginning in November.
Mrs Turia said: "Completely removing the duty-free concessions would mean that smokers, who might have a packet or two of cigarettes on them when going through Customs, had to either dump them or declare them and pay duty.''
"If they did neither, they would risk prosecution and seizure of the goods.''
The changes would raise $50 million in additional revenue per year.
Budget 2014 would allocate $2.7 million to Customs to respond to the changes.
The gift concession for tobacco - which allowed tobacco to be sent from overseas tax and GST-free - would be scrapped.
The move was one of a range of changes designed to make New Zealand smoke-free by 2025, including annual tax hikes and proposals for plain packaging of tobacco.