Three of the biggest Kiwisaver providers now have some of the lowest customer satisfaction rates.
A new survey by Consumer NZ said ASB, AMP and ANZ all had a drop in their ratings.
Only 36 per cent of ASB customers were satisfied with the service, while AMP and ANZ also scored low at 37 and 41 per cent.
Consumer NZ said it had been a bumpy 12 months for the funds because of sharemarket instability, but that was not the only reason for the drop in its survey.
Chief executive Sue Chetwin said the quality of information about the Kiwisaver funds also played an important part in pleasing customers.
Keeping clients informed about what was happening with their fund and on their options were sticking points.
Ms Chetwin said big banks in particular are default providers for Kiwisaver and get a lot of customers without a lot of effort.
"They are not looking after those customers as well as they could. I think it's too easy for they to get them [so] they are just there in a way," she said.
"They don't treat those customers as if they are customers they could lose."
Six out of 10 consumers also wanted to know whether their money is being invested ethically, the survey found.
More than 2000 New Zealanders responded to the survey that was carried out in February this year.
Milford: 66 per cent (Milford is Consumer NZ's People's Choice winner in this year's survey)
Westpac: 66 per cent
SuperLife: 60 per cent
BNZ: 57 per cent
Fisher Funds: 57 per cent
Booster: 55 per cent
Kiwi Wealth: 51 per cent
Generate: 49 per cent
Fisher Funds Two: 44 per cent
ANZ: 41 per cent
AMP: 37 per cent
ASB: 36 per cent
Mercer: 34 per cent