I have tried Googling for this but can't find an answer. Hoping someone here knows.
If someone has a full time job earning circa £25k (so in the normal range for basic NI) which is taxed and charged NI via PAYE from that employer, and then also earns circa £2k per year separately from other sources (eg music, art etc just people buying their stuff or paying for them to do something, without them having established an official "business" to market such services) then the route for paying the tax due on those additional earnings seems fairly clear - one just declares them to hmrc and gets told how much extra income tax is owed.
I don't know whether there is any additional steps needed for National Insurance. Obviously if they were earning £27k from one employer rather than £25k from one and £2k from elsewhere then they would pay £240 more NI over the course of a year. Is that £240 owed and what is the process for paying it if so? The tax self assessment only gives the option to pay the £3 per week voluntary contribution which I think is aimed at self employed people earning under the earnings limit who don't want a gap in their records. The £25k job means there isn't a gap though.
The person this affects is keen to pay what they owe but not hugely keen to pay more than they owe and doesn't understand how it is supposed to work.