Changes and issues affecting the Corporation Tax online service
These are changes and issues that may affect the way you should file your Company Tax Return.
Electricity Generator Levy (EGL)
There are currently no boxes available on the Company Tax Return (CT600) for you to submit:
- Electricity Generator Levy receipts
- the levy amounts payable
HMRC will update these on the return in April 2024.
If you need to tell us about Electricity Generator Levy receipts and the amount of levy payable before April 2024, use:
- box 986 — Energy (Oil and Gas) Profits Levy (EOGPL) amounts liable
- box 501 — EOGPL payable
Completing CT600N Residential Property Developer Tax (RPDT) and claiming RPDT group relief for carried forward losses
HMRC are aware of an online filing issue due to a restriction within the Corporation Tax online service.
You will only be affected if both the following apply:
- you’re completing Section 3 Part 3 — claims to RPDT group relief for carried forward losses on supplementary page CT600N
- you do not have a simplified arrangement in place, so you must attach notices of consent
HMRC will update the service in April 2024 to fix this issue. If you need to file your return before this date, contact your customer compliance manager.
Full expensing and 50% first-year allowances
As announced at Spring Budget 2023, companies incurring qualifying expenditure on plant or machinery on or after 1 April 2023, but before 1 April 2026, can claim:
- a 100% first-year allowance for main rate expenditure — this is known as full expensing
- a 50% first-year allowance for special rate expenditure
Find out more about full expensing.
HMRC will not update the HMRC Corporation Tax online service to support full expensing until April 2024. If you do not need to report this new relief, you can file online in the normal way before HMRC update the service.
Before April 2024, you can use the existing capital allowances boxes on form CT600 if you need to:
- submit either a full expensing or 50% first-year allowance claim, or both
- report a balancing charge online
For full expensing, use:
- boxes 725 and 750 for claim amounts
- boxes 730 and 755 to report balancing charges
- box 760 for qualifying expenditure
You should do this until we have updated the online service, and new boxes are available.
For the 50% first-year allowance, use:
- boxes 693 and 743 for claim amounts
- boxes 694 and 744 to report balancing charges
- box 773 for qualifying expenditure
HMRC will not add new boxes for the 50% first-year allowance. HMRC will amend the CT600 guide soon. You should continue to use these boxes once we have updated the online service.
You will not be able to claim full expensing or the 50% first-year allowance using the HMRC free filing service (Company Accounts and Tax Online (CATO)). We will not update the service to allow these claims.
Research and Development expenditure credit (RDEC) claims
HMRC introduced the additional information form on 8 August 2023. You must submit this for all claims for Research and Development (R&D) tax relief or expenditure credit.
Large companies
HMRC are aware that customers are unable to complete both boxes 655 and 657 on form CT600 and may get the following error:
Error 9283 — Box 655 can only be completed if at least one of the boxes 670 or 680 is greater than 0 (zero).
If you get this error, do not make entries in boxes 655 and 657.
You must still submit the additional information form to make a valid R&D expenditure credit claim.
HMRC will update the service in April 2024 to fix this issue.
Small and medium-sized enterprise (SME) subcontractor to a large company
HMRC are aware that customers who are only claiming RDEC as a SME subcontractor to a large company, are unable to complete both boxes 650 and 657 on form CT600. Completing these boxes signifies that a SME subcontractor has submitted the additional information form.
If you’re affected by this issue, you may get the following error:
Error 9281 — Box 650 can only be completed if at least one of the boxes 670, 675 or 680 is greater than 0 (zero).
If you are affected, do not make entries in boxes 650 and 657.
You must still submit the additional information form to make a valid RDEC claim.
Source: HM Revenue & Customs
It is vital that you get the details right when filing your Corporation Tax Return. If you need further assistance, please get in touch. Our experienced member of staff will be happy to help you.