Hi jamesbrittain.
Having your bank synced to your QuickBooks Online account is a great way to keep your transactions matching your bank account. I'd can help you with getting your HSBC account synced.
QuickBooks Online makes keeping your accounts up to date easy by allowing you to sync and download directly from your bank. In order to link your QuickBooks Online account you'll need to follow the steps in this article. If you are having issues finding your bank or wish to have it added you can follow the steps here.
If you have any questions let us know and we'd be happy to help.