Age Concern is selling Windsor House for around £900,000 to raise money for the charity and to allow for more flats to be built in town.
The charity has decided the time has come to sell its iconic pink house on Val Plaisant to fund the next few years after the pandemic put them in a deficit of £100,000 a year.
The planning consent given to the charity nearly 30 years ago in the 1990s stated that if the house is sold, it must be converted into flats.
Since moving across the road into the new buildings, more than 300 people live with Age Concern.
The listing on Thompson Estates shows the house is selling for £1,350,000, which is the price with the shop included.
But, the charity's chair, Ben Shenton, says it is not going anywhere.
"Our shop manager has been excellent on cutting down on the amount of storage that we have within the house, and I went in today and some of the rooms have been cleared completely.
"So we are looking for alternative storage facilities, but obviously we will need help to clear out Windsor House before we can sell it."

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