The contract to use the Nightingale hospital at Millbrook has been extended until the end of March 2021.
The £14.4 million facility was built earlier this year to care for islanders if the general hospital became overwhelmed with coronavirus patients.
It hasn't had to be used for that purpose thus far, but the lease has been extended, following a request from the Health Department, to make sure the island is prepared for a possible second wave of the pandemic.
The original lease ended on 31 July.

Medical experts acknowledge that there is still a risk of an increase of cases over the winter months, so it’s important the Government continues to listen and respond to that advice.
"The Nightingale Wing offers us security, and the knowledge that, if we are to face a second wave of COVID-19 in the Island, we have the infrastructure in place to look after our patients.
"The Nightingale Wing is Jersey’s insurance policy, and although this means an increase in cost, it is reassuring that we have a top-class facility if we need it.
"We have a much better understanding of how this virus works now, and our strategy is still to take medical advice. We will continue to implement all necessary measures to reduce the risk of spread to Islanders and protect the wellbeing of our community." - Deputy Richard Renouf, Health Minister.
Almost 900 residents in the area are being sent a letter to tell them about the extension.
No-one is currently being treated for Covid-19 in Jersey's General Hospital.
Deputy Renouf says the Nightingale wing has only been used to train some medical staff.

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