Post us your form and documents. I need to write to several organisations including banks, insurance and mortgager company to inform them of my partners death.Write to us​​ Santander Bereavement Operations, Sunderland, SR43 4FJ. Please include this Bereavement Instruction form (PDF - 97 KB) with your letter. You must then register the death with the registrar within 5 days, unless an inquest is required. Here's a step-by-step guide on how to register a death. Get up to 10 copies of the death certificate. Find out how to make an appointment, what to do after the appointment including; financial support, memorial details, and bereavement and grief guidance. Advice on informing banks, asset holders and financial organisations of a death. For guidance call us on freephone 0800 634 9494.