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HMRC internal manual

COTAX Manual

HM Revenue & Customs
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Assessing: CTSA assessments: introduction

CT Self Assessment applies to APs ending on or after 1 July 1999.

For a CTSA AP a company has to:

For APs ending after 31 March 2010, CT and CT-related payments must be made electronically and returns must be delivered online.

Every return for a CTSA AP must include a self assessment of the amount of tax which is payable by the company for that period. See COM130000 for more information about returns.

For CTSA purposes, tax is a single self assessed charge of liability under S455 CTA 2010 (Close Company Loans to Participators) and S747 ICTA 1988 (Controlled Foreign Companies), as well as mainstream CT.

Trading losses and other negative amounts are self assessable under CTSA and are determined by inclusion in the return. Under CTSA, you do not issue a loss determination to finalise the figure for an AP. See COM152000 for more information.

Where possible, claims and elections, other than those covered by Schedule 1A TMA 1970, must be made in the return or by amendment to the return.

A self assessment creates a legal charge to tax. That charge does not depend upon a judgement by an HMRC caseworker about the accuracy of the information in the return.

When a company submits its CT600 return form, accounts and computations through the CT Online Service, COTAX processes the return whenever possible and records the self assessment.

If COTAX cannot do that, it puts the case on a work list for review. A Clerical Caseworker processes the return onto COTAX and records the self assessment.

No further action is needed to at this stage. Outstanding liabilities are pursued or repayment made as required. Compliance checks are subsequently carried out to decide whether a correction should be made or an enquiry opened into the return. For more information see COM71000 onwards.

COTAX keeps a permanent record of every assessment, amendment and determination and you can view the content of each version using function DASS (Display Assessment).

If the company fails to deliver a company tax return in response to a notice to deliver, a caseworker can use function RAMA (Prepare / Amend Assessment) to determine the amount of tax payable by the company. The determination has effect as if it was a self assessment, unless and until the company delivers its return and self assessment within the relevant time limit.

Once a revenue determination charge is on the company’s record, COTAX:

  • stands it over when a return is logged
  • displaces it when a self assessment is recorded
  • reinstates it if a return that was logged on the AP is unlogged.

However, see COM131041 if the AP covered by a return does not exactly match the AP for which a revenue determination has been made.

The self assessment is final once made unless, within the appropriate time limits one of the following events happens.

  • The company amends it.
  • We correct any obvious errors or omissions.
  • We decide to enquire into the return.
  • The conclusions stated at the end of an enquiry into a return for a different period require a consequential amendment to it.

See COM23010, COM23050, COM71000 and COM23010 for more information on these events

This is subject to our right to make a discovery assessment. See COM23070 for more information.

When you have used function RAMA to make an assessment, you cannot alter it before it is issued, or stop its issue.

You must not make an assessment for a company that has been struck off.