Directors of the Island's Family Library say the facility has reached the end of the road.
In a statement, they say its services, including the building on Westmoreland Road and mobile library, will end on Friday, July 18.
Earlier this year, they revealed they needed £100,000 a year to keep the library open - sparking a desperate fundraising effort by those eager to save it.
Its closure comes despite a Tynwald decision to work with the organisation and report possible options in October.
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