If your place of business happens to be your home, whether you rent it or have a mortgage interest, HMRC permits you to claim a portion of those expenses as allowable business deductions when filing your annual tax return.
The key lies in determining the proportion of your mortgage interest or rent that qualifies as a deductible expense.
For instance, if you're working from a five-room house, HMRC typically does not consider kitchens or bathrooms as rooms for tax purposes. If you're using one room exclusively for work-related activities, it means you are utilizing 20% of your home's rooms for business purposes.
Consequently, you can claim 20% of your annual mortgage interest or rent costs when reporting your taxes.
NOTE - this rule applies to mortgage interest ONLY and it does not extend to capital repayments.