The random postal survey asks people how they prefer to pay, how often they use cash, how easy it is to deposit and withdraw coins and notes, and whether they store cash and why.
The central bank is asking new questions this year such as whether people are having challenges in using cash.
It will now carry out its survey annually instead of every two years.
"As the steward of money and cash for New Zealand, we need to ensure that New Zealanders can access, use, and bank cash," the central bank's director of money and cash Ian Woolford said.
The survey will inform its work to redesign the cash system.
Retail New Zealand chief executive Carolyn Young told Morning Report the use of cash was diminishing, to less than 10 percent of transactions.
While some people never used cash, there were times and places where it was critically important, she said.
"In rural areas versus urban areas there is more cash that goes through transactions.
"And we know intrinsically that people that are on a really tight budget, that cash is a really great tool for managing budgets."
Young said cash was indispensable in emergency situations when electricity or eftpos connections go down.
Hospitality businesses were more likely than retailers to no longer take cash, she said.
"The Reserve Bank perspective is you don't have to take cash but you have to have an alternative method if somebody can't pay by a card."
New Zealand First has put forward a members' bill to protect cash as a key option in transactions, requiring stores to take it for purchases up to $500.
Young said retailers recognised the importance of cash but didn't back it being compulsory.
There was a risk of robbery for businesses holding cash, and counterfeit notes were common, she said.
The survey runs to October 10. If people receive a letter to voluntarily participate they can check it is legitimate by visiting the Reserve Bank website, emailing cashusesurvey@rbnz.govt.nz or phoning +64 4 472 2029.
