Accurately calculating ‘Use of Home’ expenses has always been problematic even for experienced accountants due to the vagueness of HMRC guidance. The attached Excel Spreadsheet is what I consider an excellent aid for my clients and others out there. My sources are HMRC manuals and HMRC webinars. The formulas are already inserted so just plug in your figures. Don’t forget to expand the columns if necessary. Should further help be required, do get in touch.