The Department of Home Affairs says the prison has almost 15 per cent more inmates than it was designed for.
A Freedom of Information request asked how many prisoners the Jurby facility was designed to hold, and how many people were currently incarcerated there.
In its response, the department said the official capacity was 141 - and on April 7 there were 159 inmates.
It added there were 26 cabins on top of the permanent accommodation, all of which were being used.
More bus staffing problems this weekend
Bus Vannin is warning of more problems with its services this weekend.
Manx community spirit shines through during Island storms
A motorist has been praised for going above and beyond to help others after a tree came crashing down during Saturday's storms.
Free period products law receives Royal Assent
Free period products are set to become more accessible on the Isle of Man following the announcement of Royal Assent at Tynwald earlier this month.
How are Islanders supported while waiting for benefits?
A Peel MHK will ask about help for those whose benefits claims are still being processed.
Specialist vans to survey Isle of Man roads next month
The Department of Infrastructure says you may notice some unusual vans driving around the Island next month.
Great Laxey Wheel upgrades to see old ticket office removed
An old ticket office in Laxey will be knocked down ahead of new work.
MHK to question plans for improving Island's mental health services
Will mental health services be improved on the Isle of Man?
Colby Glen path shut until next April
A popular footpath in the south of the Island will remain closed until next April.
