There are tax allowances for use of your home in the course of your business, or employment. When claimed in a self-employed business it is called 'Home as Office' and is an expense used to offset profit, calculated on the percentage area of floor space occupied within the dwelling and applied to certain household expenses, such as mortgage interest (or rent), insurance, repairs and utility bills. When used in the course of employment the allowance is called 'Working from Home' and is normally claimed at a fixed daily rate up to a maximum annual limit, however, can be claimed on the actual additional household costs generated by virtue of the working, providing evidence is retained. You cannot claim simply because you choose to work at home and this must be a requirement of your job. The claim can be made for the current tax year and up to four tax years retrospectively.