If your company is claiming Research and Development (R&D) tax relief for the first time, it’s essential to understand the claim notification process. This crucial step ensures your claim is valid and processed correctly by HMRC. In this post, we cover what R&D tax claim notifications are, when they’re needed, and what happens if they’re missed.

What is an R&D Tax Claim Notification?
We previously mentioned that HMRC are applying closer scrutiny to R&D tax claims because they perceive a rise in fraudulent claims. Consequently the requirement to complete an R&D Tax Claim Notification was introduced as part of this process.
This notification alerts HMRC about your company's intentions to make a claim. Furthermore it ensures it meets all necessary requirements.
When does your company need to submit a Claim Notification?
For accounting periods starting on or after 1 April 2023, your company must submit an R&D tax claim notification if:
It’s important to understand that this requirement applies specifically to the first time you claim or if there’s been a three-year gap - see below.
Has R&D relief been claimed in the last three years?
Your company will not be required to submit a claim notification if it has made an R&D relief claim within the last three years. The three-year period is calculated from the claim notification deadline.
Firstly, the claim notification itself must be submitted within six months after the end of the accounting period. Secondly, your company must look back three years from the notification deadline.
So for example, if a company wishes to claim R&D tax relief for the period ending 31 March 2025, the notification deadline is 30 September 2025, so the relevant lookback period is 1 October 2022 to 30 September 2025.
The critical date is when the R&D claim was actually submitted, not the accounting period to which the claim relates. HMRC's guidance provides example scenarios to enable you to determine when a claim notification is needed.
How to submit an R&D claim notification
The claim notification must be filed online using HMRC’s Advance Notification Form. The notification form can be filed from the start of the period of account up until six months after the period ends.
You can complete and submit the claim notification form if you’re a representative of the company. Alternatively, this can be submitted by your accountants if they're authorised to act on the company's behalf. Therefore, make sure you’re clear on who is handling the process to avoid any confusion or errors.
What happens if you miss the Claim Notification Deadline?
If you fail to submit the claim notification on time, HMRC will treat your R&D claim as invalid. It will be removed from your corporation tax return and considered an error. This could significantly delay your claim or even cause it to be rejected entirely.
Summary
Remember to submit your claim notification within six months after the end of your accounting period. Additionally, keep track of any guidance errors or changes that may affect your submission.
However, equally importantly, always ensure you have all required information ready before filing the claim notification form.
R&D tax claim notifications are essential to ensuring your company’s claim for tax relief is processed smoothly. By understanding when and how to submit the notification, you’ll ensure your claim is validated by HMRC avoiding unnecessary delays.
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