But at the same time overseas charities have seen a boost in donations from the public and, in the wake of the charity top-ups scandal, the Government is giving a €1m Christmas funding boost to frontline charities, including €770,000 to St Vincent de Paul, €100,000 to Crosscare and €130,000 to Protestant Aid.
Charity governance agency Boardmatch Ireland has published a report on top-earning charities between 2009 and 2011 and found that they have collectively seen an 8pc decrease in funding from €3.05bn to €2.78bn.
Commenting on the findings of its report, Boardmatch chief executive Chris White said that the drop in funding was "comparatively modest when you compare it to the contraction of the overall economy in the same period".
And he pointed to a growth in funding for some overseas aid charities as proof that the public was still donating.
South Dublin hospital group St Vincent's Health Care has been named as the highest earning charity in the country with gross income of €363m in 2011. The vast majority of this funding was given by the State.
The top 10 charities in the index are dominated by hospitals, including the Mater in Dublin, St Patrick's Hospital in Cork and the Bon Secours Health System. Overall turnover for the 11 voluntary hospitals on the list declined by 8pc to €1.2bn in 2011.
A spokesman for St Vincent's pointed out that there was a distinction between the hospital group and the other charities listed.
"St Vincent's Healthcare Group has charitable status but is not a charity as a lay person would understand it," he said.
"That is, it does not give out money to the needy. It's providing healthcare services under very, very strictly monitored service level agreements with the HSE and that's what accounts for the bulk of this income that's been counted by Boardmatch."
According to Boardmatch, overseas aid agencies have, in contrast, seen a more than 10pc increase in their combined income since 2009 to €270m.
Concern Worldwide had an income of €160m in 2011, while Goal funding stood at €61m.
Unicef Ireland saw an almost doubling of its income to nearly €9m over the three years.
Meanwhile, children's disability charity the Cental Remedial Clinic, which has been at the centre of controversy over salary 'top-ups' for some executives, had funding of €19m in 2011.
Boardmatch boss Mr White said that the index "provides an unprecedented insight into the top tier of the Irish charity sector". He said his organisation would be publishing the list on an annual basis with the aim of increasing public trust in charities.
"The sector 's reputation has been severely damaged in recent times, so we feel the introduction of an annual index will play a key role in promoting a new image of charities," he said.
According to Mr White, charities that "diversified" their fundraising efforts by, for example, hosting events, using charity shops and targeting philanthropic bodies, were able to grow their income.