Self-employed people have to pay two types of National Insurance. The first, Class 2 contributions, are at a flat rate of £2.65 per week, and are paid by anyone earning more than £5,595 per year.
Class 2 payments can either be paid monthly by monthly or half-yearly, by Direct Debit, or in response to HMRC reminders. These Class 2 contributions offer very basic cover, as you'd expect from the amount of money involved.
Depending on your circumstances, these contributions may be sufficient for you to claim incapacity benefit in the future, but not industrial injuries benefit. You'll get the basic retirement pension, but not earnings-related pension payments, nor any bereavement benefits if your spouse should die.
If you don't already have the necessary form for Class 2 contributions, follow this link for all you need to know.
A contribution of only £2.65 per week may seem like a bargain, especially if you're the sort of person who prefers to rely on yourself rather than the state. But in fact this is not the end of the story.
As a self-employed person you must also pay Class 4 contributions on any profit (as calculated by your tax return form or Schedule D statement) between £7,605 and £42,475 per annum. The rate payable here is 9% of that profit, and you pay annually. You must also pay 2% on any profit over that amount.
Even this amount is less than you would pay as an employee, where around 12% of salary (between the same income levels) is the norm. With National Insurance, as with Income Tax, the self-employed generally pay less than other types of worker.