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HMRC internal manual

COTAX Manual

CT Pay and File: assessments: loss determinations (S41 TMA 70): invalid determinations

If you have made a determination for a period that you later find is not an AP, the determination is invalid.

There is no provision equivalent to S12(8) ICTA 1988 for assessments, that enables you to correct the notice.

You need to correct the AP on the COTAX record using Function MAPD (Maintain AP Dates) before making a correct determination.


  • COM152012 for a list of functions to use in particular situations
  • COM152013 for legislation applying to this subject.