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HMRC internal manual

Business Income Manual

Specific deductions: security expenditure: partial use of asset

S81 Income Tax (Trading and Other Income) Act 2005

Where an asset is intended to be used partly to improve personal physical security, only an appropriate proportion of the expenditure on the asset is to qualify for a deduction. The appropriate proportion is that attributable to the intended use to improve physical security.

If the provider intends that asset to be used solely to improve personal physical security, but there is another use for the asset which is incidental to that purpose, the trader is still entitled to a deduction of the whole of the cost or expenses. For example the cost of bullet resistant windows can be allowed in full although they have incidental non-security use in keeping out the cold.

The fact that the provision of an asset or service also improves the personal physical security of other members of the trader’s family or household does not prevent the full amount of the expenditure from qualifying for a deduction.