Sir Moses Montefiore Memorial Synagogue in Grimsby has been awarded £232,500 by Historic England to fund vital restoration work.
Built in 1885 at the centre of the port town, the shul, known as Grimsby Hebrew Congregation, is the last purpose-built synagogue in Lincolnshire and South Humberside.
Years of flooding and deterioration have left parts of the building unusable.
John Bowers, a synagogue committee member and former principal of Brasenose College, Oxford, said the funding would allow the building to be restored “back to its former glory”.
“There is an upstairs women’s gallery that we have not been able to use for many years and we have had to fence off about a sixth of the downstairs,” he said.
“If you went in you would be a bit worried the roof is going to fall down, there are strips of plasterwork falling off,” he added.
The Grimsby congregation last had a weekly minyan some 30 years ago.
It now holds an annual Yom Kippur service led by Jonathan Arkush, with most of those attending travelling from elsewhere.
Bowers said the synagogue had struggled to attract new members since its heyday in the 20th century.
With no university locally, he explained, “we don’t get a thoroughfare of people, just the odd person who happens to come to work in the town.”
Once repaired, he is hoping the synagogue will be able to host a range of events.
An exhibition on immigration to Grimsby put together by Lincolnshire Heritage, which helped with the funding application, is set to be hosted by the shul next year.
Members of the Jewish community in Lincoln visit the Grimsby synagogue, and there is another community across the Humber in Hull, but Grimsby Hebrew Congregation is the only purpose-built synagogue in the area.
The grant is part of a £41 million investment in restoring heritage buildings across England announced by the Department for Digital, Culture, Media and Sport.
The department said: “This remarkable synagogue will be supported to continue its ambitious programme of restoration, focusing on the structure of the ark within the late nineteenth century synagogue: the only remaining synagogue in Lincolnshire and South Humberside.”
Heritage minister Baroness Twycross said the funding would allow "much loved buildings" to remain open in the future.
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