A report released on Tuesday recommended using the cards, which prevent people from spending 80 per cent of their welfare money on gambling and alcohol, in Bundaberg and Hervey Bay.

But the scheme is being criticised by the opposition and the Greens for being ineffective in the West Australian and South Australian sites in which it has been operating.

Liberal senator and committee chair Slade Brockman's report accepted the measure could restrict human rights, but only to limit social harms caused by alcohol, drugs and gambling.

The inquiry found the cashless debit card had a positive effect on communities in existing trial locations.

An auditor-general report released last month found the Department of Social Services' monitoring and evaluation of the trial was inadequate.

The committee acknowledged concerns about the evaluation but said the department was taking steps to improve the process.

Labor senators said there was serious community concern about the negative impacts of the card, pointing to the inability of the government to prove it worked.

Greens senator Rachel Siewert said the bill extending the trial in Queensland would target people aged under 36, restricting their access to gift cards and money orders.

"Let's see this policy for what it really is - an ideologically driven approach, a Band-Aid solution that punishes those on income support," she said.

Senator Siewert will next week try to torpedo existing trial sites in the SA town of Ceduna, and WA's Goldfields and the East Kimberley regions.

"All of the cashless welfare card trials should be abandoned and attention focused on a comprehensive approach that addresses the underlying causes of disadvantage," she said.

Australian Associated Press