(1)This section applies for the purpose of calculating profits or other income charged to income tax.
(2)For this purpose “profits or other income” does not include—
(a)the profits of a trade, profession, or vocation,
(b)the profits of a property business, or
(c)employment income,
but see subsection (6).
(3)No deduction is allowed for any contribution paid by any person under—
(a)Part 1 of the Social Security Contributions and Benefits Act 1992 (c. 4), or
(b)Part 1 of the Social Security Contributions and Benefits (Northern Ireland) Act 1992 (c. 7).
(4)But this prohibition does not apply to an employer's contribution.
(5)For this purpose “an employer's contribution” means—
(a)a secondary Class 1 contribution,
(b)a Class 1A contribution, or
(c)a Class 1B contribution,
within the meaning of Part 1 of the Social Security Contributions and Benefits Act 1992 (c. 4) or of the Social Security Contributions and Benefits (Northern Ireland) Act 1992 (c. 7).
(6)Provision corresponding to that made by this section is made by—
(a)section 53 (in relation to trades, professions and vocations),
(b)section 272 (in relation to property businesses), and
(c)section 360A of ITEPA 2003 (in relation to employment income).