CH72520 | Penalties for Failure to Notify: Calculating the penalty: Before calculating the penalty
From HM Revenue & Customs · Compliance Handbook
To work out the penalty to be charged you will need to establish
the underlying behaviour that gave rise to the failure, see CH72100
the penalty period, see CH71200
the potential lost revenue (PLR), see CH72620
whether the disclosure was unprompted or prompted, see CH73120,
whether the failure to involve an offshore matter and the tax at stake was income tax or capital gains tax, see CH100000+, and
the quality of disclosure, see CH73220.
For detailed guidance on how to calculate the penalty, see CH73520.