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HMRC internal manual

National Insurance Manual

Co-ordinating action on Class 1A National Insurance contributions and income tax

Class 1A National Insurance contributions (NICs) are due if the conditions in NIM13020 are satisfied. One of those conditions is that there must be general earnings chargeable to Income Tax under the Income Tax (Earnings and Pensions) Act 2003, see NIM13070. If you consider that Class 1A NICs are due and Income Tax has not been paid, you should try to deal with the Class 1A NICs and the Income Tax at the same time. For more information, see DANSP46000.