One in three charities have reported a drop in their income due to scandals in the sector, according to a poll by the umbrella group The Wheel.
Some 1,600 charities represented by the organisation and other networks have called on the Government to restore State funding for social services and supports to pre-recession levels.
Responses from 64 charities to The Wheel survey this month state that since serious mismanagement and deception was revealed last June at suicide prevention charity Console, fundraising efforts have been damaged for a significant number of charities.
The revelations broadcast by RTÉ Investigations Unit resulted in the closure of Console.
Charities' representatives have been telling a pre-Budget news conference that they depend heavily on State funding to keep them out of the red while they provide public services on behalf of the Government.
The Irish Hospice Foundation says that scandals in 2013 and 2014 involving the now reconstituted CRC and Rehab resulted in a 50% drop in donations to the hospice's Christmas appeal. This year's Console scandal has also impacted on its fundraising.
Meanwhile, earlier this month, the Charities Regulator warned an Oireachtas committee that 47 charities which provide services on behalf of the State risk being downgraded because they have not completed their registration.