Internet banking services from NatWest International. A helpful list of phone numbers you might need for any banking queries with We have updated all our telephone numbers to or , to make sure it's. Useful telephone numbers Mobile Banking Helpdesk, , +44 NatWest Classic credit cards, , +44. Personal Banking Finance View in iTunes. If you have any of our contact numbers stored, please make sure you update. Loan calculator Budget calculator Salary calculator Free financial health check Money Bite. Barclays Mobile Banking Finance View in iTunes. Manage your money when it suits you, using our safe and secure services.