NIM01101 | Class 1 structural overview from 6 April 2003 to 5 April 2009: introduction
From HM Revenue & Customs · National Insurance Manual
National Insurance Contributions Act 2002
Changes were made to the structure of Class 1 NICs from 6 April 2003.
These changes were put into effect by the National Insurance Contributions Act 2002, together with various supporting regulations.
Guidance on these changes can be found at NIM01102 onwards.
The changes affect the amount of Class 1 NICs due but they do not disturb any of the existing Class 1 rules covering:
the date upon which liability arises
the methods used to assess liability or
the starting point at which liability arises.
Guidance on:
those areas of Class 1 NICs liability which are not affected by the changes and
the structure of Class 1 NICs before 6 April 2003
can be found at NIM01000 onwards.
Guidance on changes to the structure of Class 1 NICs from 6 April 2009 can be found at NIM01200 onwards.