Sustainability Assurance explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
Volume III of the ICAI Code of Ethics, Thirteenth Edition, contains Part 5 — Ethics Standards for Sustainability Assurance (Including Independence Standards). It applies from 1 April 2026 and comprises Sections 5100 to 5350 (ethics standards for every sustainability assurance engagement) and Sections 5400 to 5600 (independence standards for engagements within the scope of paragraphs 5400.3a and 5400.3b).
A third volume, and an entirely new body of standards
The Thirteenth Edition of the Code of Ethics is segregated into three volumes. Volume I is the domestic provisions and Council Guidelines; Volume II is converged with the IESBA Code, 2024 edition; and Volume III is Ethics Standards for Sustainability Assurance. The Guide to the Code is explicit on where to look: Parts 1, 2, 3, 4A and 4B are in Volume II, and Part 5 is in Volume III.
Volume III has been issued as a guideline of the Council in exercise of the power conferred under section 15(2)(fa) of the Chartered Accountants Act, 1949, as amended by the Chartered Accountants, Company Secretaries and Cost and Works Accountants (Amendment) Act, 2022. Requirements in it are designated with the letter "R" and use "shall"; application material is designated "A".
Paragraph 5100.1 states the rationale in public-interest terms: it is in the public interest that a sustainability assurance provider acts ethically "in order to maintain public trust and confidence in sustainability information that is subject to assurance." High-quality ethics and independence standards, alongside high-quality reporting and assurance standards, help investors, customers, employees, suppliers, regulators and governments rely on sustainability information in their decision-making.
The two halves of Part 5
Paragraph 5100.2 divides the Part cleanly:
| Block | What it contains | Reach |
|---|---|---|
| Sections 5100 to 5350 | Ethics standards | All sustainability assurance engagements (including those within the independence scope) and other professional services performed for sustainability assurance clients |
| Sections 5400 to 5600 | Independence standards | Only sustainability assurance engagements within the scope set out in paragraphs 5400.3a and 5400.3b |
Two fall-back rules complete the map:
- Paragraph 5100.2a — where a sustainability assurance engagement is not within the independence scope of this Part, Part 4B sets out the applicable independence standards, as set out in paragraph 5400.3e.
- Paragraph 5100.2b — a practitioner might perform professional activities and have professional and business relationships not covered by Part 5 at all, in which case Parts 1 to 4B apply to a practitioner who is a chartered accountant.
The practical reading is that Part 5 is additive, not a substitute. A chartered accountant doing sustainability assurance work is never outside the Code; the only question is which Part governs the particular activity.
What "sustainability information" covers
Paragraphs 5100.4a to 5100.4d deliberately draw the subject matter wide:
- It might be comprehensive — many topics or aspects of topics required by a sustainability reporting framework, by law or regulation, or prepared against other criteria — or limited to certain matters such as metrics, targets or key performance indicators.
- The criteria might be framework criteria, entity-developed criteria, or a combination. Framework criteria might be embodied in law or regulation, or issued by authorised or recognised bodies following a transparent due process.
- It might be prepared on a single entity or group basis, and might include information from other entities in the reporting entity's value chain.
- It might be presented in a separate sustainability report, as part of the annual report (a separately identified report, or within the management report or management commentary), or in an integrated report.
Competence is assumed at the door
Paragraph 5100.1a sets an expectation before any engagement begins: sustainability assurance providers are expected to have relevant skills, knowledge and experience to perform sustainability assurance engagements, and to have appropriate training to ensure their assurance skills are continually up to date with relevant developments. This is not a soft aspiration — it is reinforced as a requirement in Subsection 5113.
Law, sector rules and the "more stringent" test
Paragraph R5100.7 handles the collision between the Code and other rules:
"If there are circumstances where laws or regulations preclude a sustainability assurance provider from complying with certain provisions in this Part, those laws and regulations prevail, and the practitioner shall comply with all other provisions in this Part. If provisions which are more stringent or additional to those prescribed in this part have been stipulated vide any industry/Sector specific provisions, the said provisions shall be applicable with regard to such industry/Sector."
Paragraph 5100.7 A1 adds that practitioners need to be aware of differences in local regulations and comply with the more stringent provisions unless prohibited by law or regulation. In an Indian sustainability assurance engagement this matters immediately: sector regulators and listing requirements may impose obligations beyond the Code, and where they do, they govern.
Paragraph 5100.6 A3 recognises that there might be unusual or exceptional circumstances in which complying with a requirement might not be in the public interest or would lead to a disproportionate outcome. The Code's answer is not to permit a unilateral departure — the practitioner is encouraged to consult with the Institute. And paragraph 5100.6 A4 warns that acting in the public interest means considering not only the preferences or requirements of the individual client, but the interests of other stakeholders.
Breaches of Part 5
Paragraph R5100.8 splits breach handling in two. Breaches of the independence requirements are dealt with by paragraphs R5400.80 to R5400.89. For a breach of any other provision of the Part, the practitioner shall evaluate the significance of the breach and its impact on the ability to comply with the fundamental principles, and shall also:
- (a) take whatever actions might be available, as soon as possible, to address the consequences of the breach satisfactorily; and
- (b) determine whether to report the breach to the relevant parties.
Paragraph 5100.8 A1 explains that relevant parties to whom such a breach might be reported include those who might have been affected by it.
Which edition governs which engagement
The Guide to the Code sets out transitional arrangements that matter when an engagement straddles the commencement date:
| Engagement commenced | Edition applied to completion |
|---|---|
| On or after 1 April 2026 | Thirteenth Edition (2026) |
| Before 1 April 2026 (and on or after 1 July 2020) | Twelfth (2019) edition applicable from 1 July 2020 — except Sections 260 and 360, subsection 604 and paragraphs 410.3 to 410.6, for which the date of applicability is reckoned as 1 October 2022 |
| Before 1 July 2020 | Eleventh (2009) edition may be applied up to completion |
The Code adds that transitional arrangements are available in respect of specific sections.
Practical checklist before accepting a sustainability assurance engagement
- Establish whether the engagement is within the independence scope of paragraphs 5400.3a and 5400.3b — that decides whether Sections 5400 to 5600 or Part 4B governs independence.
- Identify every other professional service the firm performs for the same client; Sections 5100 to 5350 reach those too.
- Check for industry or sector specific provisions that are more stringent, and apply them.
- Confirm the team has the skills, knowledge, experience and current training paragraph 5100.1a expects.
- Map the value chain early — sustainability information may draw on entities the firm has no relationship with.
- Record which edition of the Code governs, where the engagement straddles 1 April 2026.
Common mistakes
- Treating Volume III as optional guidance. It is a Council guideline under section 15(2)(fa); its "R" paragraphs impose obligations.
- Assuming Sections 5400 to 5600 always apply. They apply only within the scope of paragraphs 5400.3a and 5400.3b; otherwise Part 4B does.
- Applying Part 5 only to the assurance engagement and not to other professional services performed for the same sustainability assurance client.
- Reading a sector rule as displaced by the Code. Paragraph R5100.7 works the other way where the sector rule is more stringent.
- Concluding a course of action is permitted because Part 5 does not prohibit it — paragraph 5120.1 exists precisely to deter that reasoning.