Almost 90% of surveyed charities in the island have reported higher operational costs compared to the same time last year.
The survey asked 60 charities in Jersey about their experiences this year compared to last and how they have changed.
Islanders are also fundraising less despite more people reaching out for charity help.
The CEO of the Association of Jersey Charities, Beth Gallichan, says the charitable sector is facing very real challenges.
"Driven by the cost-of-living crisis, they are experiencing the triple whammy of a rise in demand for their services, a decline in fundraising income with people finding it hard to donate, and an increase in their own operational costs.
The result is an unsustainable position, and we are already seeing charities making difficult decisions about reducing services.
For an island where charities play such a critical role, that would be devastating for our local communities who rely so much on them."

Around 6 in 10 charities have seen a drop in donations, and more than half have seen an increase in need for assistance.
This has led to a third of groups and organisations increasing services to meet the demand.
However, due to falls in fundraising, the same amount has had to scale back activity.
Beth says many islanders depend on local charities, but the truth is charities also depend on islanders' generosity.
"Maybe not today but at some point, you, your loved one, neighbours, our culture and wildlife have been helped or will need help.
Charities are not only here to support our community in a crisis but also to find solutions to some of our long-term challenges.
We have endured a series of community tragedies and anticipate that as inequality and poverty continue to affect more people, those that rely on charities will multiply."
Challenges will only continue into 2024, as charities anticipate the cost of providing services will increase further.
Most charities believe the government could do more in response to the cost-of-living crisis and its impact on the charitable sector.

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