More people are complaining about KiwiSaver to the Banking Ombudsman.
In its latest current account newsletter the financial services complaints scheme noted a 51 per cent increase in KiwiSaver cases compared to last year.
The scheme looked into 57 cases in the year to June 2013 including 32 enquiries, 21 complaints and four disputes.
Banking Ombudsman Deborah Battell said the majority of the complaints were about people's inability to take their money out, especially on hardship grounds.
"We think these cases may continue to increase as mortgage-related interest rates increase, the value of customers' savings in KiwiSaver schemes grows and as banks increase their share of the KiwiSaver market."
The banks control a large amount of the KiwiSaver market with the two largest providers - ANZ and ASB having a combined market share of around 47 per cent.
The Ombudsman has released a KiwiSaver guide providing information on who people can complaint to, the main types of cases it has seen, compensation and examples of certain scenarios.
People may be able to withdraw savings from their KiwiSaver account if they meet certain financial hardship requirements.
These include showing that alternative sources of funding have been explored, completing a statutory declaration on assets and liabilities and providing documented evidence to support the application.
Whether the application is approved is down to the trustee of the particular KiwiSaver scheme to which a person belongs.
If a person is not happy with how the trustee has handled their application they can complain the trustees' financial services complaints scheme.
The Banking Ombudsman is unlikely to be able to handle trustee related complaints as trustees do not belong to its scheme.