Scottish Life has warned that the stakeholder pension could lead to unequal treatment of scheme members.
In its response to the Green paper, the life offices says members who remain in a scheme could be forced to subsidise those transferring out if no penalty is involved.
It also says the proposals are overly complex and will actually increase the need for advice.
The submission adds: "We are extremely concerned that people could be encouraged to close down existing products in favour of stakeholder and, by doing so, find themselves substantially worse off".
The life office recommends that it should be possible for people to hold concurrent membership of different forms of pension schemes.