A quarter of people approaching retirement haven't worked out what they will do with their KiwiSaver nest eggs.

Of those who do know, nearly six in 10 intend to leave some or all of the savings in their Kiwisaver accounts and withdraw money as and when they need it.

KiwiSaver is still relatively young, so the amounts saved are not yet life-changing, but it seems only 17 per cent plan to pull out all of their money when they reach 65.

The rest have either come to see KiwiSaver as a longer-term investment which they will keep after they reach 65 (57 per cent) or simply don't know yet (26 per cent).

Next year, about a quarter of people over 65 will be continuing to work despite having started to receive NZ Super. That's expected to rise to nearly one in three by the mid-2020s.

With wages still coming in and NZ Super on top, many older workers are able to leave their KiwiSaver untouched, and even contribute money to it, though their employers are no longer obligated to chip in with employer contributions.

KiwiSaver providers are beginning to promote KiwiSaver as a tool for managing money in retirement, allowing people to draw down on their balances slowly over time, thereby turning it into a regular income stream.

The survey was carried out by Colmar Brunton and paid for by the Commission for Financial Capability (CFFC) and the Financial Markets Authority (FMA), which released it to coincide with Money Week.

The two organisations have been researching how well older New Zealanders are preparing for retirement. They've found a mixed picture with some very well prepared, but many others unlikely to lead more than a most basic existence after they stop work, getting by on NZ Super and little else.

The survey found room for KiwiSaver providers to provide more advice.

Only 53 per cent of KiwiSavers felt the information they were offered by providers was useful for working out how big a lump sum they'd need to generate the income they would need in retirement.

Roughly the same proportion (49 per cent) felt it was helpful in making decisions about their retirement savings.

FMA spokeswoman Simone Robbers said the message from KiwiSaver members was that they wanted to get the right kind of information and resources, in a way that was easy to understand.

"We'll continue to work with providers to ensure there is quality information available and it is more accessible. It's critical that people take some time to consider how best to preserve and use their hard-earned lump sum when they reach 65."

David Boyle, the CFFC's manager of investor education, said: "It is pleasing to see half those members who have access to their funds today view KiwiSaver as an investment option not just for saving for retirement, but to generate some additional growth and income during the years they are in retirement."

The introduction of guaranteed annuities appears to appeal to many, especially those who haven't yet saved enough for the retirement they want.

Three quarters of those nearing retirement said generating a regular income for the rest of their lives was important, but the same proportion would also want to be able to get access to that money if they needed, or wanted it, which is something traditional annuities do not allow.

Annuities provide a lifetime income, but New Zealand has not yet got an annuities market.