NIM24080 | Class 4 NICs: structure: special Class 4 NICs: general
From HM Revenue & Customs · National Insurance Manual
Section 18 SSCBA 1992
Schedule 1, Part II Categorisation of Earners Regulations 1978 and regulations 103 & 125, SS(C)R 2001
Income Tax (Earnings and Pensions) Act 2003 (ITEPA)
Section 18 of SSCBA 1992 provides for contributors who pay tax under ITEPA but who are treated by Schedule 1, Part II of the Categorisation of Earners Regulations 1978 (see ESM0122) as self-employed and are required to pay special Class 4 NICs. Examples include certain lecturers and examiners.
The calculation of special Class 4 NICs for all tax years uses the same Class 4 rates and limits as are used in the calculation of ordinary Class 4 NICs
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