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This article applies to:

  • Product: ONESOURCE Corporate Tax

April 2025 United Kingdom

We've released the following new templates for ONESOURCE Corporate Tax:
Template
FY21
FY22
FY23
FY24
United Kingdom Entity
N/A
N/A
1.335
1.289
United Kingdom Life
N/A
N/A
1.100
1.68
United Kingdom Group
1.108
1.94
1.69
1.73
United Kingdom Non-OCT
N/A
N/A
1.6
1.6
These template versions will become the default templates when you create a new calculation.

Upgrade to the latest template

When you open a calculation, you may be requested to upgrade your calculation. If you want to upgrade, select
Yes
. There is also an option to run a comparison between the old and new template. See Upgrade Templates.
If you want to upgrade to a template that isn't the latest version, select the
More
 button on the Calculation for that entity and select
Upgrade to
. See Upgrading to an Earlier Version of a Template.
You also have the option to upgrade multiple templates at the same time. See Upgrading Templates in Bulk for help.

Combined expense and income analysis sheet

Following feedback to make the software more flexible and easier to use, we added 2 new columns to the
Expense and Income Analysis
 sheet.
  • Investment business - Allowable management expenses (+)
  • Investment business - Non-allowable (+) / Non-taxable (-) management expenses
These new columns are visible when you insert the
Investment business
 sheet into the computation and lets you deal with investment business-related expenses and income on the same sheet as trade expenses and income. The separate
Investment business expense and income analysis
 sheet is no longer required. These enhancements are available in all new and upgraded FY24 computations.
These new columns become visible when you insert the
Investment Business
 sheet into the computation, letting you manage investment business-related expenses and income on the same sheet as trade expenses and income. The separate
Investment Business Expense and Income Analysis
 sheet is no longer required. These enhancements are available in all new and upgraded FY24 computations.
The
Investment business expense and income analysis
 sheet is still available but will be removed from our FY25 template, which will form part of our next release.

CT600 and supplementary forms

Updated CT600 (2025) and v1.993 schema:
 We added the new CT600 (2025) form. This latest version will be included in new computations and will replace the previous CT600 (2024) form when upgrading existing computation templates that haven't been e-filed. The main changes are:
  • Schema updated to version 1.993 to cover the changes to the main CT600 form and CT600F.
  • Added a new return type for
    Non-resident company
     to box 4 on the form.
  • A new investment zone
    East midlands
     added for the CT600M.
Updated CT600F (2025):
 This latest version of the supplementary form will be included in new computations and will replace the previous CT600F (2023) form when upgrading existing computation templates that haven’t been e-filed. The main changes to the form include the incorporation of the new managed rate for the tonnage tax and various text updates.
Updated CT600L (2025):
 This latest version of the supplementary form will be included in new computations and will replace the previous CT600L (2022) form when upgrading existing computation templates that haven’t been e-filed. The changes to the form mainly involve text updates to incorporate the new Enhanced R&D-Intensive Support (ERIS) and merged RDEC schemes.
New CT600P preparation:
 The new CT600P supplementary form for creative industries was withdrawn by HMRC shortly before this release, we’ve added the following cells to the Tax Calculation sheet to support the new boxes on the CT600 regarding the creative expenditure credit regime:
  • Box 541 - Audio-Visual expenditure credit and Video Games expenditure credit.
  • Box 614 - Audio-Visual expenditure credit / Video Games expenditure credit surrendered to this company.
  • Box 886 - Payable Audio-Visual expenditure credit and Video Games expenditure credit.
We also made the following changes to the
Utilisation of expenditure credit
 sheet to support the CT600P when it is released by HMRC (currently scheduled for April 2026).
  • The
    Corporation tax liability
     for the
    Step 1
     calculation now includes additional adjustments for SME/ERIS credits and RDEC amounts.
  • The
    Utilisation of Step 2 restriction
     section now accepts both brought forward and current period amounts to be surrendered as group relief.
  • The
    Amounts
     available for the
    Step 5
     section now includes a sub total for
    Included in current period assessment
     row and a total cell for
    Total payable to the Commissioners
     to reflect the information required in the CT600N. We also removed the
    Other
     row in this section to ensure compatibility with the forthcoming CT600N.

Corporate interest restriction (CIR)

Interest allowance b/f available in the period correction:
 We corrected an error on the
Group calculations
 sheet within the
Interest capacity
 section. The formula for
Interest allowance b/f available in the period
 changed during the Q1 2024 release to deal with the new selectors on the Interest allowance carried forward sheet for
Full interest restriction return submitted per s393(5)
? However, the formula change wasn't correct for scenarios where the interest allowance brought forward exceeded the amount that can be used in the period.
In these cases, the
Interest allowance b/f available in the period
 will be under-declared to HMRC (by the amount of
excess
 interest allowance brought forward) and the
Interest capacity
 will also be under-declared by the same amount. The CIR calculations themselves and the Interest allowance carried forward sheet are not affected. If you have a group that may be impacted, then ensure you check that the values reported to HMRC in your Interest restriction return for
Interest allowance b/f available in the period
 and
Interest capacity
 are correct and submit an amended return where necessary. The correction has been made to CIR group files for FY21, FY22, FY23, and FY24.

Creative industries

New qualifying low-budget productions 53% rate:
 You can now claim the
Independent Film Tax Credit
 (IFTC) of 53% on qualifying creative expenditure from April 1, 2024. On the
Adjustment to profit
 sheet, select
Independent film
 as the type of television or film production company and on the
Creative expenditure credit
 sheet select the
Enhanced AVEC - Independent film tax credit (IFTC)
. The relevant credit rates of the IFTC and core expenditure requirements have been included in the
Rates and limits
 section.

Fixed assets and capital allowances

Disposal of IFA excluded assets analysed as capital R&D:
 For the disposal of IFAs that have been categorised as
R&D of a capital nature
, and hence as excluded assets, a row is inserted on the TFA
Disposals analysis
 sheet to let the disposal proceeds to transfer into the correct capital allowance sheet. This change has been made for FY24.
SBA allowance statement:
 You can now print an SBA allowance statement from the
Structures and buildings allowances
 sheet by ticking the
Print SBA allowance statement?
 box. Once you have ticked the box, you can select which of your structures and buildings to include on the allowance statement. Once you have completed all the columns for each structure or building, you can print the SBA allowance statement. It is recommended that once you have printed the SBA allowance statement you revert the tick-box back to
No
 so that the
Structures and buildings allowances
 sheet shows all the columns that are relevant to the tax computation. The SBA allowance statement is available for FY24 computations.
Right of use assets note display simplification:
 In line with the changes made to the
Tangible fixed assets note
 and the
Intangible fixed assets note
 in the previous release, we updated the
Right of use assets note
 so that if you only have 1 category of assets (that is, you are only using 1 column) then only the
Total
 column will print in the final version. The ability to display and print sub-totals for each of the tangible and intangible fixed assets sections hasn’t changed and you can continue to display these sub-totals using the selector at the bottom of the page. This change has been made for FY23 and FY24.
Finance lease debtor sheet additional column added:
 We added 2 further
Other
 columns to the
Finance lease debtor
 sheet to enable more asset types to be analysed and tracked. This change has been made for FY24 only.

Life (FY24)

Iterative calculation improvements:
 We made improvements to the way the populate function and the
Iterative calculations
 sheet work:
  • A specific error message appears if the number of iterations needs to be increased for convergence.
  • Any validation errors caught during the populate process will no longer cause consequential error messages through the calculation.
  • The offset of any pre-2017 b/f LTBFC non-trading deficit is now included in the calculation on the 'Iterative calculations' sheet.
User-defined iterative elements:
 We included a new
User-defined iterative elements
 sheet that lets you link up iterative/circular figures from your own working papers into the populate function.
Investment asset improvements:
 Where there are main pool or special rate pool allowances on investment assets held for a U.K. property business, you can now claim first-year allowances against any additions in these pools. Additionally, you can now insert a
Structures and buildings allowances
 sheet for each income stream fund analysis sheet.

Oil companies

EOGPL changes from November 1, 2024:
 We updated the
Energy (oil and gas) profits levy
 sheet to reflect the following changes effective November 1, 2024:
  • Increase in Energy profits levy rate from 35% to 38%.
  • Reduction in the decarbonisation investment allowance for qualifying expenditure from 80% to 66%.
  • Removal of the main 29% investment allowance for qualifying expenditure incurred on or after November 1, 2024.
Hire cap restriction brought forward offset correction:
 The
Carried forward losses
 sheet no longer has a column for oil contractor's profits. Instead, oil contractor's profits are included within the trading profits column but are then deducted in the calculation of qualifying profits. This change has been made for FY24.

Tax accounting

Tax accounting updates:
 We made the following changes to the tax accounting sheets for FY24:
  • Updated the opening tax rate on the
    Tax rates and options
     sheet for both FRS102 and IFRS to 25%.
  • Corrected the signage of the RDEC step 2 and step 3 restriction amounts in the Deferred tax amounts not recognised section on the
    Accounts disclosures
     sheet.
  • Added more automated entries for intangibles in the
    Proof of tax
     sheet.
  • Automated the population of defined benefit pension OCI amounts in the OCI column on the
    Temporary differences
     sheet (if you select to automate the population of the Tax basis balance sheet).

Template enhancements

Intangible fixed asset importing simplification:
 We enhanced the import process for intangible fixed assets to let you populate the various IFA allowance sheets via a single import using the new
IFA Analysis
 import config file. This functionality is available for all new FY23 and FY24 computations and for existing computations when upgrading to the latest FY23 and FY24 templates. If you have an FY22 computation or a computation using older versions of the FY23 and FY24 templates, you will continue to use the existing import and reporting process, with data appearing in the original reports, such as
United Kingdom - Allowable Per Accounts Report
.

CT600L Box L75 – HMRC error

CT600L Box 75 – temporary workaround:
 The new merged RDEC rules introduced by the Finance Act 2024 were incorporated into ONESOURCE in our Q2 2024 release. At the time of the release, we were aware of an issue which we raised in the release notes as follows:
We’ve identified an issue with boxes L75 and L80 of the CT600L for periods beginning on or after April 1, 2024. It isn't clear from the guidance how the boxes are to be completed when the tax credit cap exception applies. It isn't possible at the current time to e-file your CT600L if the tax credit cap applies within your RDEC calculation due to this issue. We've contacted HMRC and await their guidance on this matter.
We received a response from HMRC on March 27, 2025 which acknowledges an error and sets out a temporary workaround until the problem can be resolved in the 2026 version of the CT600L. Unfortunately, due to this late notice, we were unable to include HMRC’s workaround in ONESOURCE for this release and the correction will be made in our next release. In the meantime, should you be affected by this scenario, contact our ONESOURCE Support team who can assist you in making the necessary changes to your computation.
note
HMRC’s updated guidance and full notes on the workaround can be found here.
The key points are as follows:
  • If you are claiming an exemption, ensure that the amount entered in Box L75 equals the amount entered in Box L70, so the amount of Step 3 restriction carried forward to the next accounting period in Box L80 is 0.
  • Add a note in your computations or in a PDF attachment with your CT return, that you are claiming an exemption under section 112E CTA 2009. We’ll update the service in April 2026 to fix this issue.

Other corrections and enhancements

Amendments for FY24 only:
  • Investment business sheet:
     Updated to ensure amounts aren't duplicated where they are analysed as
    Allowable management expenses
     on the Expense and income analysis sheet and then further analysed on another Expense and income analysis sheet.
  • Long funding operating leases sheet:
     Corrected the
    Adjustment for period
     formula when the lease is terminated.
  • Enhanced R&D-intensive support sheet:
     Note added to remind you that companies with a registered office in Northern Ireland need to consider the cap on relief under the ERIS scheme. Any tracking of this cap on a per annum basis will need to be carried out outside of the software.
  • Relevant PAYE references sheet:
     Corrected the validation relating to the format of the PAYE reference.
  • R&D allowances sheet:
    The date of acquisition is now an optional entry.
  • Structures and buildings allowances sheet:
    We added validation to prompt you to manually enter additions when you have set the
    Insert asset additions into capital allowance and IFA sheets?
     selector on the
    Permanent information
     sheet to
    No
    .
  • Loan relationships and derivatives sheet:
     A new
    Other
     column added to provide additional flexibility.
  • Profits and gains computation sheet:
    Correction of signage for
    Losses brought forward against certain investment income
     and correction for a double deduction for the same value on the
    Carried forward losses
     sheet.
  • Restricted relevant assets sheet:
     1 sheet can be inserted per each trade. This sheet was previously restricted to one per computation.
  • Overseas PE losses sheet:
     When the foreign branch exemption election is made in a computation that has been rolled forward,
    Opening negative amounts b/f
    can now be entered without having to unprotect cells.
  • Oil ring fence rates sheet:
     A new
    Other
     column added to provide additional flexibility.
  • Group module data transfer sheet:
     Correction of the formula for linking the
    Relevant intangible debits and credits – s407(1)(c) (Trading)
     rows from the
    Corporate Interest Restriction – values sheet
    .
Amendments for FY23 and FY24:
  • Capital allowance movements sheet:
     Updated to enable negative additions in certain scenarios.
  • Double tax relief sheet:
     Correction to ensure that net capital gains (and not gross) are linked from the Capital losses sheet.
  • Main pool - Overseas PE analysis & Special rate pool - Overseas PE analysis sheets:
     Corrected the formula in the
    Other adjustments to TWDV
     row in the
    U.K. trade / Residual amounts
     columns to ensure there is no duplication of amounts.
  • CT600I:
     The supplementary form can now be inserted into a file when the trade is set to
    Oil and gas production
     on the
    Adjustment of profit
     sheet. Previously, the CT600I was only available when there was a ring fence profit.
  • Investment business sheet:
     Correction of the signage of the
    Capitalised leased assets - profit (-) / loss (+) on disposal
     value, linked from the
    Capitalised leased assets
     sheet.
  • Utilisation of RDEC:
     Relevant values are now carried forward to 2 decimal places. Previously amounts rolled forward in relation to step 2 and step 3 amounts were in round pounds.
  • RDEC sheet in group:
     Corrected to ensure that all amounts claimed and surrendered are done so to 2 decimal places. Previously RDEC amounts at the group level were in round pounds.
  • CT600 boxes 772 and 773:
     Expenditure qualifying for super-deduction, full expensing, or the special rate pool equivalents now correctly linked where you have both a transfer of trade out and a cessation of trade.
  • Car lease rental restriction:
     You can now import into the
    Multiple cars
     block.
  • Structures and buildings allowances sheet:
     Mark-up added to enable migration from the legacy software.