What happened
The Financial Reporting Council has revised one UK auditing standard and one UK assurance standard so that they continue to line up with the equivalent international standards issued by the International Auditing and Assurance Standards Board. The two documents are ISA (UK) 620, on using the work of an auditor's expert, and ISAE (UK) 3000, on assurance engagements other than audits or reviews of historical financial information. Both are marked as revised in September 2026.
The change follows movement in the ethics rules that sit alongside the auditing standards. The International Code of Ethics for Professional Accountants, issued by the International Ethics Standards Board for Accountants, now sets explicit ethical requirements for how practitioners use the work of external experts in audit, assurance and non assurance engagements. The FRC's revisions bring the UK standards into interoperability with that code rather than introducing a UK specific approach.
In practice the revisions align the definitions and the responsibilities for evaluating an external expert's competence, capabilities and objectivity, so that the IAASB standards and the new ethical provisions say the same thing. They also make targeted changes to the requirements and application material in both standards, clarifying what the practitioner is responsible for when relying on an external expert and reinforcing the need for that evaluation to be properly documented.
The revised standards apply to audits of financial statements for periods commencing on or after 15 December 2026, and to assurance reports dated on or after the same date.
Why this is a GRC story
Third party reliance has moved into the ethics code. Using an external expert used to sit mostly in the technical standards. The IESBA provisions frame competence, capability and objectivity as ethical requirements, which raises the bar on what has to be documented and who is accountable for it.
The effective date lands inside current planning cycles. Fifteen December 2026 is close enough that firms mid-way through an engagement year need to decide now whether their expert evaluation process meets the revised test.
Alignment reduces cost but concentrates interpretation risk. A group operating in the UK and under IAASB standards elsewhere can run one methodology and one set of templates. The same alignment means that if a firm reads the requirement too loosely, the gap travels across every jurisdiction at once.
Findings usually land on evidence, not judgement. Inspectors rarely fault the decision to use an expert. They fault the absence of a record showing why that expert was considered competent, capable and objective at the time.
What to watch
Whether other national standard setters publish their own revisions on a similar timetable, and whether inspection findings start citing the new requirements after the December effective date. Firms should also check whether their expert onboarding templates capture objectivity and independence assessments in a form that would hold up in an inspection.
A useful exercise before year end: pull the list of external experts used on the last two engagements you audited and check whether each file documents how competence, capability and objectivity were evaluated. If that check is quick, the control is working. If it is not, it is worth fixing before the standard requires it.
Attribution: Analysis based on Compliance Week's reporting and the FRC's published revisions. This article is original commentary, not a repost of the source material.