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Troubleshooting recent changes to corporation tax returns


Published: 17 May 2021 Update History

ICAEW members have highlighted issues they have experienced following updates to the corporation tax return (CT600) on 1 April 2021, including trouble accessing an additional page relating to research and development claims.

As previously reported in tax news in brief on 7 April 2021, a new supplementary page (CT600L) needs to be completed on corporation tax returns from 1 April 2021.

The new page covers claims or amendments to claims under the SME research and development tax relief regime and the Research and Development Expenditure Credit scheme.

ICAEW’s Tax Faculty has been told that some agents are having trouble completing the supplementary page because the tax software they are using has not yet been updated to allow it to be generated.

If you are experiencing such issues, the faculty advises that you speak to your software provider to find out when they will be resolved. In the meantime, HMRC advises that you file the corporation tax return form, including the CT600L by post if you cannot wait for digital access.

If you do post in a return remember to post everything required including the CT600, CT600L and any other supplemental pages plus fill in form WT1 explaining (in Box 6) that your software provider has not updated yet and placing WT1 on top of the return.

This should be sent to: Corporation Tax Services, HM Revenue and Customs, BX9 1AX, UK.

It is also worth noting that the latest version of the CT600 (also released on 1 April) contains boxes relating to the receipt of COVID-19 related support, including:

  • details of claims under the Coronavirus Job Retention Scheme and the Eat Out to Help Out (EOTHO) scheme (boxes 471–474);
  • overpayments due as a result of these schemes (box 526); and
  • EOTHO reimbursed discounts included as taxable income (box 647).

This is new information that agents will not be used to obtaining from clients so should be factored into requests for information processes.

As with the updated CT600L, agents should check with their provider whether their tax return preparation software provides a facility to complete these.

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