1018-500 Payment and repayment of Class 4 contributions
Class 4 contributions are normally collected through the same self-assessment system as income tax under ITTOIA 2005.
SSCBA 1992 directs that the provisions of the Income Tax Acts about assessment, collection, repayment, recovery and, in particular, penalties apply to Class 4 contributions as if they were income tax due under ITTOIA 2005, Pt. 2, Ch. 2. The new penalty regime for under-declared earnings in FA 2007, Sch. 24 introduced with effect from 6 April 2009 for returns of 2008–09 profits applies equally to Class 4 contributions (see para. 30).