R&D tax relief: Notify first, claim later

Companies planning to make an R&D tax relief claim should be aware of an important deadline.

For companies with a 31 December 2025 year end, the deadline for submitting an R&D claim notification form, where required, is 30 June 2026.

This means that if your company is planning to claim R&D tax relief for the year ended 31 December 2025, you should urgently check whether you need to notify HMRC before the deadline.

What is the R&D claim notification form?

The R&D claim notification form is used to tell HMRC in advance that a company is planning to make a claim for R&D tax relief or expenditure credit.

It is separate from the R&D claim itself. The notification form does not replace the company tax return, the R&D claim calculation, or the additional information form that must usually be submitted before the R&D claim is made.

Instead, it is an advance notification requirement. If a company is required to submit the form and misses the deadline, the R&D claim for that period may be invalid.

Who may need to submit a notification?

A claim notification form may be required if the company is planning to claim R&D tax relief or expenditure credit for an accounting period beginning on or after 1 April 2023 and either:

1. the company is claiming R&D tax relief for the first time; or

2. the company’s last R&D claim was made more than 3 years before the last date of the claim notification period.

There are also some exceptions and detailed rules, so it is important to check the position carefully rather than assuming that a notification is or is not needed.

What information is needed?

The claim notification form asks for information including:

• The company’s Unique Taxpayer Reference.

• The contact details of the main senior internal R&D contact, such as a company director.

• Details of any agents involved in the R&D claim.

• The accounting period start and end date.

• The period of account start and end date.

• A high level summary of the planned R&D activities.

The notification form does not require the full evidence and detail that will be needed for the R&D claim itself, but the information still needs to be accurate and consistent with the eventual claim.

Do you still need to submit an additional information form?

Yes. The claim notification form and the additional information form are not the same thing.

The additional information form is a separate requirement and must be submitted before, or on the same day as, the company tax return containing the R&D claim. If the additional information form is submitted on the same day as the company tax return, it should be submitted first.

The additional information form requires more detailed information about the R&D projects, qualifying expenditure, and the basis of the claim.

What should you do now?

If your company has a 31 December 2025 year end and is considering an R&D claim, you should check now whether a claim notification form is required.

This is particularly important if:

• you have not claimed R&D tax relief before;

• your previous R&D claim was several years ago;

• you are unsure when your last R&D claim was made;

• your business has started new development work during the year; or

• you are planning to claim but have not yet prepared the full R&D report or company tax return.

Missing the notification deadline could prevent a valid R&D claim from being made, even where the underlying project would otherwise qualify.

If you are unsure whether the notification rules apply to your company, or you need help preparing and submitting the notification form, please contact us as soon as possible.