Hi Stephen,
Class 2 NIC is a voluntary National Insurance payment, where the net turnover (net profit) is below the 'small profits threshold for the year.
In 22/23, 23/24 & 24/25 this threshold is £6275.
If your net profit exceeds this sum, then £3.45 is compulsory and is payable for each week you traded (£179.40 per annum).
It is collected through self assessment.
Class 4 NIC is payable where your net profit exceeds £12570.
3. Class 2 and Class 4 National Insurance (self-employed)
Thank you