One in five bank customers have been offered financial products that they did not need according to Consumer NZ's latest banking survey.
The most common products promoted included credit cards, increases in credit card limits, personal loans and life insurance.
Consumer NZ said the majority of people offered the products did not think it was a good option or suited their needs.
The annual survey also found 16 percent had felt pressured by bank staff into buying a financial product they did not need.
Consumer NZ's head of research Jessica Wilson said pressure selling by banks was a major concern, given it could lead to consumers unnecessarily going into debt or being sold a poor-value product.
"Banks have attracted a lot of bad press in the past 12 months for their selling practices and we would have expected to see a change in behaviour. However, our survey results don't give us any confidence that's happening," she said.
Ms Wilson told Morning Report there wasn't anything wrong with banks letting customers know about their products.
"The issue here is that banks are promoting these products to people who don't think they're suitable for them," she said.
"Banks have obligations to be responsible lenders."
There needed to be better regulation and closer monitoring of banks, she said.
"No one's been keeping tabs on banks' behaviour and that needs to change."
The country's largest bank ANZ was the worst offender for pushing unwanted products.
The survey also found just 47 percent of consumers thought banks could be trusted while 68 percent felt profits in the industry showed banks were charging too much.
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