Quick answer: The CIRD Manual is HMRC's internal guidance on Corporate Intangibles Research and Development, covering the R&D definition, qualifying expenditure, the SME, RDEC, merged and ERIS schemes, and enquiry handling. It is not legally binding, but it is the working reference HMRC officers and most specialist advisers use.
What is the CIRD Manual?
The CIRD Manual, short for Corporate Intangibles Research and Development Manual, is HMRC's published internal guidance on the corporate intangibles regime and the R&D tax reliefs. It covers the statutory definition of R&D, qualifying expenditure categories, the operation of the SME, RDEC, merged and ERIS schemes, subcontracting rules, compliance procedures and enquiry handling. Although not legally binding, the manual is the working reference used by HMRC officers and by most specialist advisers.
Where is the CIRD Manual published and how is it structured?
The manual is published on GOV.UK at hmrc-internal-manuals/corporate-intangibles-research-and-development-manual. The R&D sections begin at CIRD81000. Key references include CIRD81300 for the meaning of R&D, CIRD82000 onwards for qualifying expenditure, CIRD89700 for RDEC, CIRD90100 for the merged scheme, and CIRD90700 for ERIS.
What does using the CIRD Manual look like in practice?
An adviser preparing a claim for a software company references CIRD82500 for cloud and data costs, CIRD84000 for externally provided workers, and CIRD81300 for the underlying R&D definition. The manual provides the standard framework of references used in both the written claim narrative and in any subsequent correspondence with HMRC, allowing the position to be grounded in a citation trail that an HMRC officer will recognise.
Worked example: building a claim narrative from CIRD references
A £600,000 SaaS claim under the merged scheme cites CIRD81300 for the underlying advance-and-uncertainty test, CIRD82500 for £120,000 of cloud costs, CIRD83000 for £380,000 of staff costs, and CIRD84000 for £100,000 of externally provided worker costs at the statutory 65% restriction. At the 20% merged-scheme rate, £600,000 of qualifying expenditure supports a £120,000 pre-tax credit. For comparison, HMRC recorded 46,950 total R&D claims in 2023-24 worth £7.6 billion in aggregate relief - a blended average of around £162,000 per claim - so a well-documented, CIRD-referenced claim of this size sits close to the national average.
Why the citation trail matters on enquiry
When HMRC opens an enquiry, one of the first things a caseworker checks is whether the claim narrative maps cleanly onto the manual’s own section numbers - a claim that cites CIRD82000 onwards for each cost category, rather than describing costs in general terms, is faster to defend. Advisers preparing qualifying expenditure schedules routinely keep a CIRD reference against every cost line for exactly this reason. Advisers who keep a running CIRD-reference log throughout the accounting period, rather than reconstructing it at claim time, typically produce a faster and more defensible claim narrative, since each cost line can be tied back to the specific manual section that supports its inclusion.
Related terms
Frequently asked questions
No. HMRC's own manual guidance is not statute, but it reflects the practical positions HMRC officers apply on enquiry, and departing from it without a documented reason increases enquiry risk.
It covers the statutory definition of R&D, qualifying expenditure categories, the operation of the SME, RDEC, merged and ERIS schemes, subcontracting rules, compliance procedures and enquiry handling.
The manual is published on GOV.UK, and the R&D sections begin at CIRD81000, with CIRD81300 covering the meaning of R&D, CIRD82000 onwards covering qualifying expenditure, CIRD89700 covering RDEC, CIRD90100 covering the merged scheme, and CIRD90700 covering ERIS.
A claim narrative that maps cleanly onto the manual's own section numbers is faster to defend on enquiry than one that describes costs only in general terms.