Roy Morgan's Pip Elliott said a breakdown of the data showed coffee drinkers in some parts of the country were more picky when it came to their caffeine fix.
"Caffeine-fiends" in Wellington spent the most on fresh coffee, but South Islanders forked out the most for all types of coffee, she said.
A higher proportion of Wellingtonians visited cafes for coffee and tea than Aucklanders, which surprised her.
"So much for the popular conception of Auckland as the buzzing heart of Kiwi cafe society," Ms Elliott said.
The statistics have been backed up by Nielsen figures, provided by the Food and Grocery Council of New Zealand (FGCNZ)
In the year to April Kiwis spent almost $112 million on instant coffee at supermarkets, down 5 per cent.
In comparison, supermarket sales of roasted and ground coffee rose 3 per cent to $47.8 million. Flavoured coffee jumped 9.5 per cent to $43 million.
Katherine Rich, chief executive of FGCNZ, said a change of business culture - with more meetings taking place in coffee shops and cafes - may have contributed to a shift in drinking habits.
"I think New Zealand has a very well-developed cafe culture, because those of us who were children of the 70s and 80s remember when asking for a 'long black' drew a blank stare," she said.
Mark Treviranus, general manager of Atomic coffee in Auckland, also believed Kiwi coffee drinkers are developing more sophisticated taste-buds, and opting for the good stuff regardless of price.
"I think it comes down to quality and taste," he said. "As people become more educated [about coffee] their palettes are more educated in terms of coffee and what tastes better."
Connoisseur's $60 a week habit
John Corfield has binned instant in favour of "proper coffee" and now spends between $60-$100 a week.
As an electrician in England, John said he regularly drank instant "because it was quick and easy", but four years ago, when he embarked on a backpacking trip around the world, his eyes were opened to more than just different cultures.
"I started going round to free Wi-Fi hotspots and that's when I found proper coffee," he said. " After a bit of time, I discovered you can't beat a real coffee. And I started, every time I went somewhere new, to try and find a good coffee shop."
The 34-year-old says living in New Zealand for the past three years has developed his taste for a freshly brewed coffee.
He uses both a plunger and a stove-top maker to brew his own; most of his spending goes on take-away coffees and in coffee shops.
