The final shape of the child trust fund remains unclear.
The joint Treasury and Inland Revenue team has taken more than two years to develop the proposals but has failed to conduct any qualitative research on who will use the funds.
A bill was included in the Queen's Speech but no decision has been made on charges. Several major providers have said they would be unwilling to make a commitment to the funds if they are forced to offer them at 1 per cent.
The scheme is set to launch early next year, with 250,000 babies born on or after September 2003 getting an initial endowment. The Treasury has released no details on the level of subsequent top-ups.
The Building Societies Association believes 25 per cent of societies may be excluded from the plans because they cannot offer the equity-based option.
BSA head of savings policy Brian Morris says: “We hope that by the time this bill is introduced, the Treasury will have taken on board the concerns of building societies. Any organisation that wants to play a part in making CTFs a success should be able to do so. In addition, there needs to be a real consumer choice especially for those who need a risk-free fund because they can ill afford to lose their initial deposit.”