Metadata costs a 'big ballpark'

The cost of setting up Australia's new metadata storage regime remains a "big ballpark" estimate even after the legislation has become law.

Communications minister Malcolm Turnbull says talks are continuing on how much will be funded by government and what costs will fall to internet service providers.

"We've said we will pay a substantial portion of the (set-up) costs and one of the six factors that we're taking into account is the size and capability of particular ISPs," Mr Turnbull told reporters in Melbourne.

"Obviously Telstra or Optus or iiNet or TPG have got much greater capacity to do this than a smaller internet service provider but that is an ongoing discussion ... between government and the industry.

"The estimate that we've received - and it's a broad one - is roughly $200 to $400 million in capital cost to set it up.

"Clearly that's a big ballpark and there's a lot more work being done on that at the moment."

Mr Turnbull said once the system was running, ongoing costs would be covered by the same user-pays arrangement now in place for law enforcement agencies accessing telecommunications data under a warrant.