People are being urged to seek financial help as soon as they find themselves struggling as a result of the Covid-19 pandemic.
The Financial Services Complaints service, funded by registered financial service providers, expects complaints to increase by as much as 30 percent once government and lender support packages come to an end.
"We know from experience of previous hard economic times, for example the 2008 Global Financial Crisis, that complaint numbers rise," chief executive Susan Taylor said.
She said some people may suddenly find themselves out of work and unable to cope with debt repayments and other financial commitments as a result of the pandemic.
Taylor said people should ask their bank or other lender for hardship relief and check whether there was any government assistance available.
Borrowing from friends and family or making a withdrawal from a KiwiSaver plan were other options.
"While it is sometimes possible to access your KiwiSaver funds due to significant financial hardship, the criteria for doing this is stringent and generally the consumer will need to have explored every potential avenue before an application can be considered by a KiwiSaver supervisor," she said.
Taylor said not being able to draw on KiwiSaver for some relief was a source of complaints.
"It is important to remember that there is a reason for this high threshold to meet when seeking an early release of KiwiSaver funds."
In any case, Taylor said people should get independent financial advice and take care to read the small print before agreeing to any debt relief package.