SolvedCSLM10124 | FAQs: employers questions and answers: do I include tax credits as income?
From HM Revenue & Customs · Collection of Student Loans Manual
Suggested answer
No. Tax credits are not treated as income for Student Loans and or Postgraduate Loan (PGL) purposes.
For student loan and or PGL purposes only include earnings as you would calculate for employer’s secondary class 1 NIC purposes.