Situated overlooking St Helier's waterfront and marina, the hotel joins Longueville Manor within the select group of five-star properties on the island.
The Grand Jersey was bought by property investment company Delancey in 2006 for £15.5m from De Vere Group and has since spent a further £15m on upgrading the property.
Anna Dowling, managing director of the hotel, said she was delighted by the award. "It is a testament to the hard work, dedication and commitment of our team that we have achieved this premier ranking, Following the hotel's refurbishment we have spent the past 12 months working very hard to ensure that we achieve this aspirational fifth star.
"We have continued to invest in training, product standards and maintain staffing levels despite the difficult economic climate. It has always been our aim to provide guests with an exceptional experience by striving to give the highest levels of service."
By Janet Harmer
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