A friend of mine carried out two days of work for a company and submitted an invoice for payment (a relatively small sum of less than £200).
The company has come back and asked to amend the invoice to add her UTR and NI numbers with a statement declaring she is liable to pay her own tax & NI. My friend is not self-employed and has never submitted a self-assessment (and therefore has no UTR), is claiming Universal Credit and is currently unable to work due to illness.
I understand the company wants this information to cover themselves but is it strictly necessary? I have suggested that she just updates the invoice with the statement saying she is liable to pay her own tax and NI but decline to provide a UTR and NI number. My friend however is worried that they won't pay if she doesn't provide it (the invoice is for work done quite a long time ago in a previous financial year but she only submitted the invoice this year, so the company is actually being accommodating by agreeing to pay it). She is also worried that registering as self-employed may affect her benefits. Due to illness and other factors, it is fairly unlikely that she has earned enough money this tax year to pay any tax (in this year or in the year she actually did the work).
Does anyone have any suggestions on what she should do? I know that probably both she and the company should have done their homework before engaging with each other, but it's all too late now!