Since August 2023, HMRC have introduced two key documents related to the submission of R&D tax relief claims – the Additional Information Form (AIF) and the Claim Notification form (CNF).
These two forms have caused no end of upset and confusion, with more than a handful of missed claims. Confusion has been caused by the forms being very similar, but also very different.
The timing of the introductions has also caused problems with the AIF immediately being required for all claims, and the CNF being tied to accounting period dates and as such, taking longer to come into common usage.
Here’s our quick guide to the differences between the forms, when to use each one, and where to go for help and guidance.
The key difference between the AIF and the CNF is their purpose. The AIF was introduced as a way for HMRC to gather additional information about all claims in order to reduce error and fraud within the scheme, and enable inspectors to more easily identify which claims met the eligibility criteria.
Conversely, the CNF was introduced as a way to gather high-level details about the claims before it is submitted, allowing HMRC to get an understanding of the number and types of claims in the pipeline, and to carry out early interventions where claims are less likely to be eligible, for example, for companies with less technical SIC codes.
Alongside this, the form prevents first time claimants claiming for two years at once making these companies less attractive to less ethical R&D tax advisors.
Another major difference between the forms is when they should be submitted. Where needed, a CNF has to be submitted within the claim notification period, running from the first day of the claim period to six months after the end of the claim period.
The AIF, on the other hand, must simply be submitted before the CT600 for the relevant accounting period. This can be any time within the two years after the end of the accounting period and is tied to the CT600 amendment deadline.
All claims require and AIF to be submitted before the CT600. Claims without an accompanying AIF will be rejected. The situation for the CNF is a lot more complicated and covered in detail here.
In brief, a CNF is only required for claim periods starting on or after 1st April 2023, and only for companies who have either not claimed before, or whose last claim was submitted more than three years before the end of the claim notification period.
There are some important exceptions to this rule, where claims that were submitted in the window but rejected by HMRC after an enquiry and claims for accounting periods starting before 1st April 2023, but submitted as an amendment after this date not counting as previous claims for this purpose.
The CNF is fairly basic, requiring only identifying information about the company, it’s advisers, and a high-level description of the R&D projects.
The AIF is a lot more extensive, requiring detailed information about some or all of the projects included in the claim, as well as detailed breakdowns of the costs.
Thus far no, there is no link between the two forms, and HMRC do not appear to be using the information from the CNF when assessing the information provided in the AIF. No information is carried over from the CNF to the AIF automatically, and having submitted a CNF has no effect on the requirement to submit an AIF.
Both of the forms can be accessed through the gov.uk website and have strikingly similar looking pages and portals (another major source of confusion).
The AIF is here and the CNF is here.
In both cases, the button to access the portal is at the bottom of the page, below a lot of very helpful guidance about how to fill out each respective form. Further guidance about the AIF can be found in CIRD182000 and the CNF in CIRD180000.
In both cases, a missing form means an invalid claim. In the case of the CNF, if a CNF is required and not submitted within the claim notification window the claim is lost, and there’s nothing that can be done.
In the case of the AIF, if a claim is submitted without an AIF it will be rejected, but as long as there’s still time to amend the CT600 the claim can be resubmitted with an accompanying AIF, and HMRC should accept the submission.
With stricter HMRC oversight, accountants and advisers need a process that leaves nothing to chance. WhisperClaims keeps you on track with tailored guidance, risk assessments and expert Advice Line support, helping you submit robust claims, and keeping you confidently on the right side of HMRC.
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