Clerys Department Store is to reopen on 21 November, after it ceased trading in July due to storm damage.
In a statement, the retailer said the building had been completely restored.
Clerys Managing Director Dominic Prendergast said: "Following four months of extensive refurbishment work, the 160-year-old retail emporium that is Clerys had been restored to its former glory."
All 86 staff who were temporarily laid off in August will be taken back on, the company confirmed.
