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HMRC internal manual

Debt Management and Banking Manual

Interest: Interest Review Unit (IRU): Corporation Tax (CT): General background

Corporation Tax (CT) and associated liability

This section deals with guidance on CT, Section 419 Assessing, Loss and ACT Carry-back in CT; ‘Advance Corporation Tax (ACT); and Income Tax- Company Payments (IT-CP)’.

The ‘assessing’ of CT and its linked duties falls into several separate categories. These are:

Type of CT Assessing periods covered Found under
Corporation Tax Assessing (CTA) All assessing periods up to and including those ending on 30 September 1993 (30 June 1999 for S419 assessments). CCOL and CASS on IRIS
(via Other Corporate Apps on ISSO)      
  Corporation Tax Pay and File (CTPF) Accounting periods from 1 October 1993 to those ending on 30 June 1999. COTAX on ISSO
  Corporation Tax Self Assessment (CTSA) Accounting periods from 1 July 1999 onwards. COTAX on ISSO
  Section 419 Assessing Accounting periods up-to and including those ending on 30 June 1999.  

From 1 July 1999 onwards found as separate assessment in the respective COTAX record.

(via Other Corporate Apps on ISSO)      
  ACT and IT-CP Accounted for under the form CT61. CACT and FHIS on IRIS.
(via Other Corporate Apps on ISSO)

There is now very little activity on ACT through form CT 61 as this has not been used since 1999. ACT may appear through an investigation and be assessed through CCOL. Activity continues in respect of IT-CP through form CT61 but because these are rare, there is no direct guidance on handling interest objection for these Heads of Duty.