CSLM11263 - FAQs: borrowers questions and answers: only income is unearned but I have an SA return
Suggested answer
When you receive your SA return at the end of the year you should complete it in the normal way as regards tax.
However, the return will also contain boxes to confirm that you are a Student and or Postgraduate Loans borrower, to enter the amount of repayments due and to ask for your loan and or plan type. If you do not know your loan and or plan type you can find out by logging into your online account.
If the only income on the return is unearned then you still may be liable to make repayments if the total income exceeds the threshold during the year.
You can find more information on gov.uk.