The study, commissioned by Charity Logistics and undertaken by consultants Z/Yen, was due to have been completed by the end of March, but has now been put back two weeks.
Z/Yen and the Active Community Unit will issue a joint questionnaire to voluntary organisations. Once the data has been collected, the two bodies will write separate reports.
The Charity Logistics study will consider whether an insurance mutual is a good idea for charities, while the unit will analyse a range of practical solutions to the sector's insurance problems that will be put to ministers.
The insurance industry will also be asked to respond.
Sector umbrella groups the Charity Finance Directors' Group, ACEVO and the Institute of Fundraising have all supported the feasibility study.
George Cook, chief executive of Charity Logistics, said: "A number of highly influential organisations are now getting behind this initiative.
While this may mean we incur a slight delay at the start of the survey, the fact that so many people are supporting it should ensure that we will end up with a report that offers the best solution for the sector."
A Charity Commission spokesman said: "We welcome practical initiatives aimed at addressing the difficulties concerning the provision of insurance.
"We will be watching with interest what conclusion the study reaches about the interesting possibilities of an insurance mutual for charities and the role of risk management clubs in reducing the cost of premiums."