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HMRC internal manual

COTAX Manual

CT Pay and File: assessments: arithmetical and other errors in assessment

COTAX automatically corrects any arithmetical errors in the figures captured from the return form CT200 when you make an assessment for a CT Pay and File AP, using Function

  • PASR (Prepare Assessment Based On Return)


  • PAST (Prepare Full Assessment)

In both functions, COTAX shows you a draft assessment calculated from the captured figures, containing

  • The figures captured from the return in blue on the left of the screen. You cannot change these figures


  • Any arithmetical errors, corrected, on the right of the screen in black on a yellow background.

You can change entries or make new ones, using the [Amend] button. Full details are included in the COTAX Online Help (COSH).

Note: COTAX does not let you enter a figure which

  • Is arithmetically incorrect


  • Does not comply with its validation rules. For example, if you attempt to change the Financial Years so that they are not correct for the AP

COTAX changes your figures to the correct ones and redisplays them to you using the appropriate colour combination (Word 28KB)

For a list of forms relevant to this subject, see COM151021.

For a list of functions to use in particular situations, see COM151011.