From April 2015 your liability to pay Class 2 National Insurance Contributions (NICs) as a sole trader or self-employer person will be assessed annually when you submit your self assessment tax return. Payment will be made at the same time as your payment for tax and Class 4 NICs. …

Business owners who are sole traders will probably have an accounting year which ended on 31st March. This date is in line with HMRCs tax year which ended on 5th April. …