The ICM poll of more than 1,000 individuals found that 31 per cent believe that charities' main purpose is to encourage people to volunteer and give to good causes. Only 16 per cent believe that charities' most important role is to campaign and raise awareness.
The NCVO says there is growing concern in the voluntary sector that the Government and opposition parties value charities mainly because of their ability to deliver good quality public services.
Its chief executive, Stuart Etherington, said it was important that this should not be the only role the Government cared about: "While the role of charities in helping the vulnerable and needy with the public's support or as part of the welfare state is widely acknowledged, for many it's their role as civil society organisations that enable us to be more community minded that matters most."
Almost half (48 per cent) of respondents to the poll think that charities should be paid the full cost of providing public services. Another 25 per cent believe that they should be paid more so they can invest in other charitable activity. A similar proportion (23 per cent) say charities should be paid less than the full cost.
The survey, the first to look at this issue, is to be published at the NCVO's annual conference today.