(1)All the provisions of the Income Tax Acts, including in particular—
(a)provisions as to assessment, collection, repayment and recovery, and
(b)the provisions of Part X of the [1970 c. 9.] Taxes Management Act 1970 (penalties),
shall, with the necessary modifications, apply in relation to Class 4 contributions under this Act and the Northern Ireland Contributions and Benefits Act as if those contributions were income tax chargeable under Case I or Case II of Schedule D.
(2)Subsection (1) above is subject to any provision made by or under—
(a)sections 17(3) and (4) and 18 below;
(b)sections 17(3) and (4) and 18 of the Northern Ireland Contributions and Benefits Act; and
(c)Schedule 2 to this Act.
(3)Schedule 2 to this Act has effect for the application or modification, in relation to Class 4 contributions under this Act and the Northern Ireland Contributions and Benefits Act, of certain provisions of the Income Tax Acts, and the exclusion of other provisions, and generally with respect to the contributions.
(4)The Inland Revenue shall, at such times and in such manner as the Treasury may direct, account to the Secretary of State for, and pay to him—
(a)the sums estimated by the Inland Revenue (in the manner so directed) to have been collected by them as Class 4 contributions under section 15 above and section 15 of the Northern Ireland Contributions and Benefits Act; and
(b)so much of any interest recovered by the Inland Revenue by virtue of paragraph 6 of Schedule 2 to this Act as remains after the deduction by them of any administrative costs attributable to its recovery.
(5)So much of any money received by the Secretary of State under subsection (4) above as is estimated by him, in accordance with any directions of the Treasury, to represent Class 4 contributions collected, or interest in respect of such contributions recovered, from persons in Northern Ireland shall be paid over by him to the Northern Ireland Department.