BIM42101 - Measuring the profits (specific rules & practices) - receipts & deductions: deductions - scope of: starting point

What can be deducted?

You cannot deduct expenditure in computing the profits of a business for income tax purposes if, either:

1. it falls within the scope of any of the prohibitions specified in The Taxes Acts (for example entertaining, ITTOIA05/S45-S47 or CTA09/S1298-S1300), or
2. it is not a proper debit item to be charged under ordinary commercial principles against the incomings of the business in computing the balance of the profits.

See