The federal government's estimate of $467 million in costs relating to the implementation of SuperStream is higher than most industry participants expected.

The costs relate to the upgrade of back-office systems and data standardisation of superannuation funds, but they represent only the amount the government will spend on the implementation of the new systems.

It does not reflect the costs super funds will have to bear themselves.

The government said in yesterday's federal budget that it would seek to raise the $467 million through a levy on Australian Prudential Regulation Authority-regulated super funds over the coming seven years.

The levy is estimated to be $121.5 million in 2012/13, $111.1 million in 2013/14, $83.1 million in 2014/15, $69.3 million in 2015/16, $41.2 million in 2016/17 and $40.9 million in 2017/18.

Association of Superannuation Funds of Australia chief executive Pauline Vamos said the cost estimates came as a surprise as the legislation had not yet been finalised.

"The absolute imperative of any levy is that they are transparent and that their use is accountable," Vamos said.

"We are still negotiating to ensure this policy is effective, so how can you assess the cost of implementation if you don't have the final legislation?

"This sits on top of the Trio levy and this sits on top of the implementation costs that the funds will have to bear. It is quite enormous.

"The flow-on implication is that it will come out of members' accounts."

Deloitte partner Russell Mason said the levy itself did not come as a surprise, as the government had flagged the costs before, but he agreed the amount was probably higher than expected.

"The amount is quite large. One can only hope that in the new financial year, detail around the SuperStream legislation will be coming forth shortly," Mason said.

The IQ Business Group chief executive officer Graham Sammells, who has been part of the government's SuperStream working group, was also surprised by the scale of the levy.

"It is a big number, but it also shows a commitment to the program," Sammells said.

The Australian Institute of Superannuation Trustees (AIST) had a more stoic attitude towards the levy.

"We had expected that there would be costs and it is pretty much in line with what were our expectations," AIST chief executive Fiona Reynolds said.

"It's important that these reforms are adequately funded."

Reynolds said she was more concerned about the methodology through which the levy would be charged.

"There is no clarity about how it will be spread out, but obviously we would like to see that there is some equity within the size of the funds, the funds under management and the number of members," she said.

"AIST will be consulting with the government to ensure any levies are calculated on a fair and equitable basis for all super fund members."