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HMRC internal manual

Business Income Manual

Specific deductions: administration: National Insurance contributions

S53 Income Tax (Trading and Other Income) Act 2005, S1302 Corporation Tax Act 2009

No deduction is allowed in computing the taxable profits of a trade for any National Insurance contributions paid by any person other than secondary Class 1 contributions, Class 1A contributions and Class 1B contributions.

Where primary Class 1 contributions are deducted from employees’ salaries the above rule does not deny a deduction for the gross salaries (ie before deduction of the contributions).

For guidance on National Insurance contributions generally see the National Insurance Manual.