Culture Vannin says its income from lottery duty fell by four per cent last year.
The Manx Heritage Foundation has published its annual report for the last year, which will be laid before Tynwald in February.
In it, it says the Treasury cut its funding by £5,000 last year to £104,000 while contributions from lottery duty fell to £372,488.
Chairman Chris Thomas says the organisation has set up three reserve funds to help distribute grants and maintain its financial footing.
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