The financial regulator has called out the big banks for "unreasonably delayed" and in some cases "legalistic" fees-for-no-service reviews.
ASIC says Westpac, ANZ, NAB, Macquarie and AMP have yet to complete reviews of systemic fees-for-no-service failures beyond those already reported since 2013.
That's despite the regulator advising them to conduct them in 2015 or 2016.
Commonwealth Bank completed its further reviews but told the Australian Securities and Investments Commission in December it would look into whether three of its licensees had extracted fees-for-no-service.
ASIC commissioner Danielle Press said the size of the reviews - which go back six to 10 years and cover 36 licensees from six institutions that currently authorise more than 7,000 advisers - did not excuse the sluggish response.
'These reviews have been unreasonably delayed," Ms Press said.
"ASIC acknowledges that they are large scale reviews ... however, we believe the institutions have failed to sufficiently prioritise and resource their reviews."
She said the main reasons for the delays included poor internal record keeping and inadequate methodologies such as some institutions proposing to make customers opt in to a review and remediation program.
"Some institutions have taken a legalistic approach to determination of the services they were required to provide," Ms Press said.
She welcomed the government’s commitment to give ASIC new directions powers that could speed up future remediation programs.
The charging of fees for services that customers didn't need, couldn't access or didn't know they were entitled to was one of the major scandals heard by the financial services royal commission.
While CBA is reviewing its three licensees, Macquarie estimates it will complete its review by mid 2019 and AMP in the second half of 2021.
ANZ, NAB licensee JBWere and Westpac licensees Magnitude and Securitor have not given ASIC their proposed target dates for completion.