KiwiSaver accounts are set to swell under a new arrangement allowing New Zealand citizens who move back from Australia to bring their retirement savings with them.
New Zealanders working in Australia have had their compulsory superannuation contributions locked up until retirement age, but a law change in Australia in November has cleared the way for them to transfer their money to a KiwiSaver scheme.
The change, which was confirmed by both prime ministers on Saturday, will take effect from 1 July.
The Australian superannuation system holds about $A16.6 billion in accounts which are inactive.
Auckland University retirement policy and research centre co-director Michael Littlewood said it won't be to everyone's advantage to consolidate their savings in one country.
He said those who leave their money in Australia run the risk of their pension fund losing track of their contact details.