THE Positive Action Group believes charities are "discriminated against" by banks.
The political lobby group believes charities only receive a "meagre" level of investment income and said they should be given parity with individual investors.
The group's call comes at the start of National Ethical Investment Week.
The PAG said the recently published Index of Charities lists about 700 registered charities working in the Island.
It said the larger ones have to bear the cost of employing paid staff to ensure continuity of their day to day activities while most of them are kept afloat by a group of committed, enthusiastic unpaid volunteers who work tirelessly, raising funds for their particular cause.
It added all charities need to hold money which is accessible in short term interest bearing savings or current accounts which are regarded as corporate accounts by most deposit takers.
PAG chairman Roger Tomlinson said: "We are very fortunate in the Isle of Man to have an energetic Third Sector, giving freely and generously of time and effort to good causes.
"Certain charities receive excellent support from financial institutions but there is no automatic recognition by deposit takers that charities merit a reasonable rate of interest on their deposits.
"In fact the opposite, they are discriminated against. It seems to me that banks on the Island are missing a trick in this area of their corporate responsibility.
"I can deposit money in my own name and receive considerably more interest on it than a charity would.
"It doesn't make sense when so many individuals are involved in voluntary work and the deposits are simply the combined deposits of private individuals.
"PAG calls for at least one financial institution to create a special high interest account for IoM charities which are such an important component of the fabric of Manx society.
"This ought to be something within the control of local banks. We don't believe it would cost very much at all. At the end of the day, why should charity deposits be discriminated against?
"Having talked to a few local community groups removing this discrimination would be of tremendous benefit to the Third Sector."
