The bank claim that footfall into its physical stores is “at an all-time low, with no signs of it returning” as many customers choose online banking instead.
HSBC also said it would use cash saved from the closures to invest in its remaining branches.
There are several HSBC branches across the Channel Islands: Guernsey has three branches on the Bridge, the High Street and in St. Martins.
Alderney and Sark have one apiece, on Victoria Street and Rue Lucas respectively.
The island is now left with just one physical bank – HSBC.
Jersey has four branches of HSBC; two in St. Helier, one in St. Brelade, and one in St. Saviour.