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HMRC internal manual

Business Income Manual

Specific deductions: rent and rates: business rates

Business rates are payable in respect of non-domestic premises. If part of the premises is used for domestic and part for non-domestic purposes, the charge is limited to the non-domestic part. Business rates are therefore usually an allowable deduction in computing trading profits or property income.

If, exceptionally, the premises, or those parts of the premises, chargeable to business rates are in fact used for non-business purposes, a proportion of the expenditure should be disallowed.