Customers have been informed that the Five Oaks and Halkett Street branches will shut, following the refurbishment of the one on King Street.
The Halkett Street branch will close in January 2024 and the Five Oaks branch the following August.
HSBC says no jobs will be lost as part of the change.
The bank's spokesperson, Cameron Senior, said: "The way people bank is changing - something the pandemic has accelerated. We know from our review that the majority of customers have a preference to do much of their day-to-day banking digitally, and while we’ve seen a significant reduction in the number of customers using our Halkett Street and Five Oaks branches, we’ve developed a model that provides islanders with both the opportunity for face-to-face servicing as well as online banking products and services."
The St Brelade branch will also shut its doors for three months at the end of 2024, while refurbishment works take place.
The King Street bank is currently closed until January while it undergoes a facelift.
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