More than a million KiwiSaver members have a large portion of their money invested in bonds yet many aren't aware of it.
Research by regulator the Financial Markets Authority has found a low level of awareness for bonds - a type of investment where companies and governments borrow money from investors and pay interest for the loan of that money.
The FMA says around $15 billion is in KiwiSaver conservative and default funds - much of which is invested in fixed interest investments including bonds.
But in a survey it undertook just four out of 10 KiwiSaver members knew that most funds invest in bonds.
The FMA did the research as part of Money Week, which launched on Monday and is focusing on debt this year.
Paul Gregory, head of investor capability at the FMA, said while some people invested directly in bonds most people were invested through KiwiSaver.
"We wanted to check to see whether New Zealanders realised this, and how much they knew about bonds."
Only 52 per cent of those surveyed knew that bonds were a type of debt.
Two thirds of people said they were confident their money would be paid back yet less than half knew the credit rating of the bond - a key which points investors to the likelihood of the debt being paid back.
There was also greater uncertainty about other features. Of those surveyed only 38 per cent knew bonds were not guaranteed.
Only 39 per cent knew bonds did not keep their original value if sold before the maturity date - the date at which the money is due to be paid back to the investor.
Gregory said investing in bonds was often associated with greater certainty and lower risk.
"But that's not always the case."
Gregory said when interest rates rise, as they are doing now, bond values tend to fall which may cause some conservative and default funds to have negative returns.
"It is important investors are not unnecessarily surprised if that happens to their bonds in those conditions.
"Don't panic. Don't sell or switch out just because you have some negative returns. Think about whether you're still on track for your longer-term goals before making any decisions."