The survey asks sector leaders whether there are specific projects they could deliver if they had more access to finance, what types of finance they are most interested in and what terms would be acceptable to them.
The survey will remain open for at least a year, and data from it will contribute to the creation of a range of funds.
Jonathan Jenkins, chief executive of the SIB group, said: "From managing more than 1,000 relationships with investors over the past 10 years, we know a good deal about their financing needs, but to make sure our new funds have the maximum impact we need to hear from more sector organisations about what they need finance for and what sort of deals look attractive to them."
Jenkins said earlier surveys had shown that about 20 per cent of organisations wanted more than £1m in funding and the majority were looking to scale an existing programme.
He also said that there was more appetite for equity-like finance – products that resemble stocks and shares, where the level of repayment to the investor is dependent on the success of the charity.