The confederation says only primary care trusts and strategic health authorities should have to consult on the planning and provision of services and on 'significant proposals' to change the way services are provided and operated.
Foundation and other provider trusts should instead have a duty to involve users, deputy director of policy Jo Webber said.
The Local Government and Public Involvement in Health Bill, which had its second reading in the House of Commons this week, says that all four types of organisation should consult.
She said: 'This is an issue of commissioners versus providers. Commissioners need to consult because they are required to develop strategic needs assessments and develop their prospectuses.
'Providers need to involve patients in what they are delivering and feed back about how it's working or not working.' She said that should involve 'a different range of questions'.
The bill's proposals are being interpreted as a response to the legal row over North Eastern Derbyshire PCT's decision to commission GP services from independent provider UnitedHealth Europe. The PCT was censured by the High Court for failing to consult adequately on its proposals.
Under the new bill, the health secretary may also demand a PCT report on its consultation and the influence of results on its commissioning decisions.
Ms Webber said: 'Certainly, after Derbyshire, clarification was needed about what was meant by consultation. I think [the bill] will clarify this but we will need to look at the guidance associated with it.'
She welcomed other parts of the bill, which will strengthen local area agreements, abolish patients' for-ums and the Commission for Patient and Public Involvement in Health and introduce local involvement networks (LINks) with a remit to cover health and social care in a local area.
She said: 'We welcome the new LINks and in particular how they will fit in with overview and scrutiny committees. The whole system starts to build together and that's what people want.'
The LINks proposals hit controversy in the Commons. Shadow health minister John Baron said they would lack the independence and ringfenced funding of pre-decessor organisations. Where patients' forums had the power to inspect services, LINks will have a right to enter and view.
He said: 'We contend that that falls well short of the power to enter and inspect. There is a big difference, and the bill does not make it clear that the powers that patients' forums have will be matched by those of the new LINks.'
Health minister Rosie Winterton defended the proposal, saying: 'We listened to what members of patients' forums said and agreed that there should be a right of entry to premises.'