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Policy Brief No. 34

Mandatory tax adviser registration in the UK (brief)

This paper sets out research and the publisher's opinion. Factual statements are cited to their sources. It makes no allegation about any firm or person not named in a cited official record.

A short account of the UK requirement, introduced in 2026, for paid tax advisers who deal with HMRC for clients to register, what it means for research and development relief claims, and what it leaves out.

ResearchCreditIntegrity.org is operated by SR Tax Services LLC under the Swanson Reed brand. Swanson Reed is an R&D tax advisory firm with a commercial interest in how R&D tax advisers are paid. See our conflicts of interest statement.

Key points

  1. Before 2026, anti-money laundering supervision was the only legal requirement to set up as a UK tax adviser, and HMRC named specialist R&D agents among its concerns.1Source 1HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026).
  2. Under the Finance Act 2026, a business paid to interact with HMRC about another person's tax affairs must register for an agent services account, in stages from 18 May 2026.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).3Source 3HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10800, "When tax advisers must register and transitional arrangements" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10800 (accessed 11 October 2026).
  3. The conditions concern supervision, the adviser's own tax compliance, convictions, sanctions and insolvency; none requires a qualification or professional body membership.4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).
  4. HMRC can suspend registration, including for up to 12 months for falling below its standard for agents, and can penalise and bar advisers who keep interacting while unregistered or suspended.5Source 5HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30400, "Sanctions and safeguards: financial penalties for prohibited interactions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30400 (accessed 11 October 2026).6Source 6HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30200, "Sanctions and safeguards: suspensions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30200 (accessed 11 October 2026).
  5. Registration does not concern fees, and an adviser who works on a claim without dealing with HMRC need not register.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).

Why registration was introduced

HMRC's March 2024 consultation said that anti-money laundering supervision was "the only legal requirement needed to set up in business and provide tax advice and services", so practitioners could enter the market "without demonstrating minimum standards of competence".1Source 1HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026). It named "some specialist Research and Development (R&D) agents" alongside some repayment agents and promoters of tax avoidance as sources of substandard advice.1Source 1HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026).

The consultation published HMRC's analysis of 500 R&D claims from its first random enquiry programme. Where the agent belonged to a professional body, 20 percent of the cost of relief was non-compliant; where it did not, 53 percent was. HMRC cautioned that the groups differ in size and claim value.1Source 1HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026).

The government received 426 responses, and 79 percent of those answering the question supported mandatory registration.7Source 7HM Revenue and Customs, Raising standards in the tax advice market: summary of responses (30 October 2024), Foreword and sections 3 and 4. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/outcome/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration-summary-of-responses (accessed 11 October 2026). It decided that from April 2026 all practitioners who interact with HMRC for a client must register, and left the wider question of how to regulate standards open.7Source 7HM Revenue and Customs, Raising standards in the tax advice market: summary of responses (30 October 2024), Foreword and sections 3 and 4. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/outcome/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration-summary-of-responses (accessed 11 October 2026).

What the law requires

HMRC's manual explains that section 224 of the Finance Act 2026 defines a tax adviser as an organisation or individual which, in the course of a business, assists other persons with their tax affairs, including by helping prepare any document HMRC is likely to rely on.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026). Registration is required where the business both interacts with HMRC about another person's tax affairs and is paid for it. Filing a claim or other document counts as interaction.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026). The legal entity registers; HMRC checks its "relevant individuals".2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).

Statutory exceptions include in-group advice, acting in appeals to a court or tribunal, and responding to HMRC requests for information.8Source 8HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10300, "Exceptions to the registration requirement" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10300 (accessed 11 October 2026). Registration opened in tranches: new advisers and those without existing HMRC agent accounts from 18 May 2026, those with Self Assessment or Corporation Tax agent accounts from 18 August 2026, and later dates for payroll and financial services businesses.3Source 3HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10800, "When tax advisers must register and transitional arrangements" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10800 (accessed 11 October 2026).

The conditions

The business must show approved anti-money laundering supervision. It must not have relevant unfiled returns or unpaid tax outside a payment plan, be subject to an HMRC refusal to deal with it, an anti-avoidance sanction or a stop notice, have relevant unspent convictions for fraud or tax offences, be formally insolvent, or be suspended or banned from registering.4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026). Relevant individuals must meet the same conditions and must not be disqualified as directors.4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026). To stay registered, the business must also act consistently with HMRC's standard for agents.9Source 9HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR20200, "Standards expected of tax advisers" (updated 3 June 2026), section "Compliance expectations". https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar20200 (accessed 11 October 2026).

Enforcement

A registered adviser can be suspended for failing a condition, until the failure is put right, or for falling below the standard for agents, for up to 12 months. A suspended adviser cannot submit claims, respond to compliance checks or contact HMRC for clients by any channel.6Source 6HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30200, "Sanctions and safeguards: suspensions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30200 (accessed 11 October 2026). Interacting while unregistered or suspended leads to a compliance notice and then penalties of £5,000 for each prohibited interaction, rising to £10,000, followed by temporary and then permanent ineligibility orders.5Source 5HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30400, "Sanctions and safeguards: financial penalties for prohibited interactions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30400 (accessed 11 October 2026).10Source 10HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30500, "Sanctions and safeguards: ineligibility orders" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30500 (accessed 11 October 2026). HMRC may publish details of sanctioned advisers.11Source 11HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30520, "Power to publish details of sanctioned tax advisers" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30520 (accessed 11 October 2026). HMRC says the regime is meant "to support compliance rather than punish genuine mistakes".12Source 12HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30100, "Overview of HMRC's approach to sanctions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30100 (accessed 11 October 2026).

What it means for R&D claims

An agent must log in to an agent services account to submit the additional information form that every R&D claim needs.13Source 13HM Revenue and Customs, Additional information you must submit before you claim Research and Development tax relief, sections "When to submit" and "Who can submit". https://www.gov.uk/guidance/submit-detailed-information-before-you-claim-research-and-development-rd-tax-relief (accessed 11 October 2026). An adviser paid to submit that form, a claim notification or the return is interacting with HMRC and must register.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).13Source 13HM Revenue and Customs, Additional information you must submit before you claim Research and Development tax relief, sections "When to submit" and "Who can submit". https://www.gov.uk/guidance/submit-detailed-information-before-you-claim-research-and-development-rd-tax-relief (accessed 11 October 2026). The claim notification asks for the contact details of all agents involved, including any that gave advice, analyzed costs or helped prepare technical assessments.14Source 14HM Revenue and Customs, Tell HMRC you want to claim Research and Development (R&D) tax relief, section "What information you'll need". https://www.gov.uk/guidance/tell-hmrc-that-youre-planning-to-claim-research-and-development-rd-tax-relief (accessed 11 October 2026).

An adviser that works on the claim but leaves every interaction with HMRC to the company or to another registered adviser is outside the requirement.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026). It may still be a tax adviser for the separate sanctionable conduct penalty, which applies, for conduct from 1 April 2026, where an adviser intends to bring about a loss of tax revenue.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).15Source 15HM Revenue and Customs, Compliance Handbook, CH176100, "Sanctionable conduct by tax advisers: Overview", and CH176140, "Commencement date" (manual updated 7 October 2026). https://www.gov.uk/hmrc-internal-manuals/compliance-handbook/ch176100 (accessed 11 October 2026).

What it does not cover

Registration does not test competence: no condition requires a qualification, an examination or professional body membership.4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026). It does not concern fees: no condition addresses how an adviser is paid. HMRC's standard for agents says agents should make clear in their terms "how the agent is to be paid for their services", but the standard does not replace the law.4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).16Source 16HM Revenue and Customs, The HMRC standard for agents (updated 9 February 2026), introduction and section 4.3.3. https://www.gov.uk/government/publications/hmrc-the-standard-for-agents/the-hmrc-standard-for-agents (accessed 11 October 2026). The professional rules of the Chartered Institute of Taxation and the Association of Taxation Technicians say contingent fees "can carry increased risks", but bind only their members.17Source 17Chartered Institute of Taxation and Association of Taxation Technicians, Professional Rules and Practice Guidelines (updated 1 January 2021), paragraph 8.2.1. https://www.att.org.uk/sites/default/files/PRPG%20%28Update%201.1.2021%29%20-%20Final.pdf (accessed 11 October 2026). HMRC states that a customer who uses a tax agent remains responsible for its own tax affairs.18Source 18HM Revenue and Customs, Approach to Research and Development tax reliefs 2023 to 2024 (published 30 October 2024), section 2.5. https://www.gov.uk/government/publications/hmrcs-approach-to-research-and-development-tax-reliefs-2023-to-2024/approach-to-research-and-development-tax-reliefs-2023-to-2024 (accessed 11 October 2026).

What the record shows

The UK now requires every paid adviser who deals with HMRC for a client to register and meet conditions, and gives HMRC the power to cut off those who do not.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).6Source 6HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30200, "Sanctions and safeguards: suspensions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30200 (accessed 11 October 2026). The change responded in part to concerns about specialist R&D agents.1Source 1HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026). It gives HMRC a register and checks on advisers' own conduct; it does not measure competence, reach advisers who never deal with HMRC, or address how advisers are paid.2Source 2HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).4Source 4HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).

References

  1. HM Revenue and Customs, Raising standards in the tax advice market: strengthening the regulatory framework and improving registration (consultation, 6 March 2024), chapter 3 and Annex C. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration (accessed 11 October 2026).      Back
  2. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10100, "Scope and requirement to register: who must register as a tax adviser" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10100 (accessed 11 October 2026).           Back
  3. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10800, "When tax advisers must register and transitional arrangements" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10800 (accessed 11 October 2026).   Back
  4. HM Revenue and Customs, Check if you meet HMRC's conditions to register as a tax adviser (last updated 2 October 2026), sections "Who needs to meet the conditions" and "The registration conditions". https://www.gov.uk/guidance/check-if-you-meet-hmrcs-conditions-to-register-as-a-tax-adviser (accessed 11 October 2026).         Back
  5. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30400, "Sanctions and safeguards: financial penalties for prohibited interactions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30400 (accessed 11 October 2026).   Back
  6. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30200, "Sanctions and safeguards: suspensions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30200 (accessed 11 October 2026).    Back
  7. HM Revenue and Customs, Raising standards in the tax advice market: summary of responses (30 October 2024), Foreword and sections 3 and 4. https://www.gov.uk/government/consultations/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration/outcome/raising-standards-in-the-tax-advice-market-strengthening-the-regulatory-framework-and-improving-registration-summary-of-responses (accessed 11 October 2026).   Back
  8. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR10300, "Exceptions to the registration requirement" (updated 18 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar10300 (accessed 11 October 2026).  Back
  9. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR20200, "Standards expected of tax advisers" (updated 3 June 2026), section "Compliance expectations". https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar20200 (accessed 11 October 2026).  Back
  10. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30500, "Sanctions and safeguards: ineligibility orders" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30500 (accessed 11 October 2026).  Back
  11. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30520, "Power to publish details of sanctioned tax advisers" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30520 (accessed 11 October 2026).  Back
  12. HM Revenue and Customs, Mandatory Tax Adviser Registration manual, MTAR30100, "Overview of HMRC's approach to sanctions" (updated 14 August 2026). https://www.gov.uk/hmrc-internal-manuals/mandatory-tax-adviser-registration/mtar30100 (accessed 11 October 2026).  Back
  13. HM Revenue and Customs, Additional information you must submit before you claim Research and Development tax relief, sections "When to submit" and "Who can submit". https://www.gov.uk/guidance/submit-detailed-information-before-you-claim-research-and-development-rd-tax-relief (accessed 11 October 2026).   Back
  14. HM Revenue and Customs, Tell HMRC you want to claim Research and Development (R&D) tax relief, section "What information you'll need". https://www.gov.uk/guidance/tell-hmrc-that-youre-planning-to-claim-research-and-development-rd-tax-relief (accessed 11 October 2026).  Back
  15. HM Revenue and Customs, Compliance Handbook, CH176100, "Sanctionable conduct by tax advisers: Overview", and CH176140, "Commencement date" (manual updated 7 October 2026). https://www.gov.uk/hmrc-internal-manuals/compliance-handbook/ch176100 (accessed 11 October 2026).  Back
  16. HM Revenue and Customs, The HMRC standard for agents (updated 9 February 2026), introduction and section 4.3.3. https://www.gov.uk/government/publications/hmrc-the-standard-for-agents/the-hmrc-standard-for-agents (accessed 11 October 2026).  Back
  17. Chartered Institute of Taxation and Association of Taxation Technicians, Professional Rules and Practice Guidelines (updated 1 January 2021), paragraph 8.2.1. https://www.att.org.uk/sites/default/files/PRPG%20%28Update%201.1.2021%29%20-%20Final.pdf (accessed 11 October 2026).  Back
  18. HM Revenue and Customs, Approach to Research and Development tax reliefs 2023 to 2024 (published 30 October 2024), section 2.5. https://www.gov.uk/government/publications/hmrcs-approach-to-research-and-development-tax-reliefs-2023-to-2024/approach-to-research-and-development-tax-reliefs-2023-to-2024 (accessed 11 October 2026).  Back