Claim super-deduction and deal with asset disposals where super-deduction has been claimed in Corporation Tax
Super-deduction
The 2021 Budget introduced super-deduction for expenditure incurred by companies between 1 April 2021 and 31 March 2023. These changes are summarised in HM Revenue and Customs Guidance: Super-deduction:
From 1 April 2021 until 31 March 2023, companies investing in qualifying new plant and machinery assets will be able to claim:[Super-deduction]
a 130% super-deduction capital allowance on qualifying plant and machinery investments a 50% first-year allowance for qualifying special rate assets
To find out more, refer to HM Revenue and Customs Guidance: Check if you can claim super-deduction or special rate first year allowances.
note
According to its Super-deduction Factsheet, HMRC considers the 130% super-deduction and the 50% special rate first-year allowance to be First Year Allowances.
HM Revenue and Customs added boxes to the 2022 CT600 for super-deduction. Corporation Tax versions 22.0 and 23.0 contain these boxes for super-deduction, but do not automatically write back to these boxes. We intend to add this function later. Until then, you can use the following alternative method to add the rates manually.
important
If you use this alternative manual method, we strongly recommend you review the return when we make automatic writebacks are available. This will help you to make sure you report super-deduction to HMRC and deal with future disposals correctly.
Alternative method using version 22.0 or 23.0 — add super-deduction and special rate first-year allowance manually
- Sign in as an administrator.
- Go toTools,Manager, thenComputation Parameters.
- Select theCA Ratestab.
- For Special Rate Assets:
- In the row beneath the current details, enter01/04/2021as theStart Date.noteCorporation Tax changes theEnd dateon the row before and entersongoinginto the row you're editing.
- For theEnd date, replaceongoingwith31/03/23.noteThis is the last date on which expenditure will qualify for the relief.
- Enter50in theFYA %column.noteCorporation Tax adds the other rates.
- For General Pool:
- In the row beneath the current details, enter01/04/2021as theStart Date.noteWhen you enter aStart Datein a new row, Corporation Tax updates theEnd Dateon the row above and entersongoingas theEnd Dateof your new row.
- For theEnd date, replaceongoingwith31/03/23.
- Enter130in theFYA %column.

- SelectOK.
- When you enter an item in the General Pool or Special Rate Pool with a date from 1 April 2021 to 31 March 2023, mark theFYAcheckbox to apply the new rates.importantIf you the markFYAcheckbox, don't also complete theAIAbox.When you enter items in the Special Rate Pool with theFYAcheckbox marked, Corporation Tax does not automatically complete theQualifying Additionstab in theFixed Assets Reconciliation Summary.
- If you entered an item in the Special Rate Pool with theFYAcheckbox marked:
- Go toAccounts, thenFixed Assets Reconciliation Summary.
- SelectDetails.
- Select theQualifying Additionstab.
- In theSpecial Rate Poolrow, replace theAutoitem with the correct amount.
importantCorporation Tax completes boxes705 (allowances)and760 (Machinery and plant on which FYA is claimed), but you'll need to manually adjust the boxes on the CT600. How you do this depends on your version of Corporation Tax. - To manually adjust boxes if you use Corporation Tax versions 22.0 or 23.0:
- Right-click box705and selectEnable Editingfrom the context menu.
- Change the amount to remove the part that relates to the super-deduction.tipIf you need to remove all the allowance amounts in this box, you can pressSpace barto clear entire box.
- Select box691 (Machinery and Plant - super-deduction)and enter the amount.
- To complete the boxes for the special rate allowance:
- Right-click box695and selectEnable Editing.
- Change the amount to remove the part that relates to the super-deduction.
- Select box693 (Machinery and Plant - special rate allowance)and enter the amount.
- For the expenditure:
- Right-click box760and selectEnable Editing.
- Change the amount to remove the part that relates to the super-deduction.
- Manually add the amounts to box772 (Machinery and Plant - super-deduction)and box773 (Machinery and Plant - special rate allowance)as needed.
noteThese steps cover the most common scenario where capital allowances affect the trading profits calculation, but you can use the same process for capital allowances that affect non-trading profits and if there are balancing charges. The boxes are:- Super-deduction allowances:691 (trade)and741 (non-trade).
- Special-rate allowances:691 (trade)and743 (non-trade).
- Super-deduction balancing charges:692 (trade)and742 (non-trade).
- Special-rate balancing charges:700 (trade)and744 (non-trade).
- Qualifying Expenditure:773 (super-deduction)and773 (special rate allowance).
note
On 8 November 2021, we reported that HMRC gave the following advice on their Corporation Tax Service Availability page:
If you do need to submit a super-deduction and/or 50% first-year allowance (SR allowance) claim or report a balancing charge online before April 2022, it is possible to do this utilising existing capital allowances boxes. For CT600, boxes 725 and 750 can be used for claim amounts, boxes 730 and 755 can be used to report balancing charges and box 775 can be used for qualifying expenditure until the online service has been updated and new boxes are available.
Enter disposals of assets where super-deduction was claimed
- Manually calculate the balancing charge for the asset.noteFor details, refer to HMRC Guidance: Disposing of a super-deduction or special rate first year allowance asset to work out the balancing charge.
- Create a new user-defined pool for each disposal of this type:
- Go toCapital Allowances.
- SelectAssets.
- In theOther Capital Allowances Claimedfolder, selectUser-defined Assets.
- SelectNew.
- Enter anAsset Name.
- SelectAdd Row.
- Enter the originalAddition Date.
- Enter 0 for theCost / B Fwd.
- Enter theDisposal Date.
- Enter theProceedsamount (this is the balancing charge for the asset you calculated earlier).
- SelectCalculate Allowance.noteCorporation Tax will show the disposals in the computation under a separate section forOther Assetsand the disposal and balancing charge amounts as the same figure. You may want to add a note to confirm these are super-deduction amounts and explain how you calculated the balancing charge. To add a note under theOther Assetssection in computation:
- Select theUser-defined Assetsfolder.
- SelectNotes.
- Enter a note heading and text.
- If the disposal is of an asset where the Special Rate First Year Allowance has been claimed at 50% or where the allowance was not claimed in full, you'll need to go to the Special Rate Pool (or General Pool) and dispose of the portion of the asset in that pool.noteFor example, a company boughty an asset for £100,000 in accounting period ending 31/12/21, where it claimed the Special Rate First Year Allowance at 50%. The company sold the asset for £50,000 in the following accounting period. You would need to enter £25,000 as a balancing charge in a user-defined pool, and £25,000 as a disposal in the Special Rate Pool.
- These steps will complete box730on CT600, but you'll need to take the following steps to move the amount to the new boxes:
- Right-click box692 Super-Deductionor694 Special Rate Allowanceas needed, then selectEnable Editingfrom the context menu.
- Enter the balancing charge in one or both of these boxes, as needed.
- Select box730and either pressSpace barto remove the amount or, if there should be other items in the box, replace it with the correct amount.
noteIf the capital allowances don't relate to a trade, Corporation Tax will complete box755on the CT600, and you'll need to take the following steps:- Right-click742 Super-Deductionor744 Special Rate Allowance, then selectEnable Editingfrom the context menu to enter the amount there.
- Select box755and either remove the amount or, if there should be other items in the box, replace it with the correct amount.
Add a note if you applied the alternative method in version 21.2 or earlier
You can add a note to your computation that explains you've used an alternative method to claim the super-deduction and why the company could not wait for the 2022 CT600 form. To add this note:
- Go to theCapital Allowance Explorer.
- Select the pool folder.
- SelectNotes.
- Enter your note, then selectOK.
- SelectClose, thenOK.
When you next open the computation, the note will show under the relevant pool section.