ESG Reporting with GRI & ISSB for SMEs: Which Standard, What to Disclose (2026)

What ESG reporting is, and why the standard you pick matters

An ESG (or sustainability) report is how a company discloses its Environmental, Social and Governance impacts and performance in a structured way. A common SME mistake is writing a "nice-looking" report with no standard — the result is not comparable, not verifiable, and easily labelled greenwashing.

Two families of international standards dominate, and the key point is that they do not replace each other — they serve two different audiences:

• GRI (Global Reporting Initiative) answers: how does the company affect the outside world? It is the most widely used sustainability reporting standard, with over 10,000 reporters across more than 100 countries (Global Reporting Initiative).
• ISSB (IFRS S1 & S2) answers: how do sustainability matters affect enterprise value and cash flows? — i.e. it serves investors (IFRS Foundation).

SMEs don't need to "do both standards" at once. Decide who reads your report — customers and community → start with GRI; investors and banks → head toward ISSB. The good news: the two standards are being made interoperable.

How GRI and ISSB differ

Audience: GRI serves all stakeholders; ISSB (IFRS S1/S2) serves investors and capital markets. Materiality: GRI uses impact materiality (the company's impact on the economy, environment, people); ISSB uses financial materiality (effect on enterprise value) (GRI). The EU (CSRD/ESRS) combines both as double materiality (Deloitte, 27 Jun 2024).

Scope & timing: GRI is structured as Universal (GRI 1, 2, 3 — 2021), Sector, and Topic Standards. IFRS S1 & S2 were issued 26 June 2023, effective for annual periods beginning on/after 1 January 2024, subject to each jurisdiction's adoption, with first-year transition relief (climate-only / Scope 3) (IFRS Foundation).

Table 1 — GRI vs ISSB (IFRS S1 & S2) compared

Criterion	GRI Standards	ISSB — IFRS S1 & S2
Primary audience	All stakeholders (customers, community, employees, investors…)	Investors & capital markets
Materiality principle	Impact materiality — the company's impact on the economy, environment and people	Financial materiality — effect on enterprise value
Disclosure scope	Broad: E, S, G across the Topic Standards	S1: sustainability in general; S2: climate specifically (incl. Scope 1, 2, 3)
Timing / effective date	Universal 2021 edition (GRI 1, 2, 3); continuously updated via Topic/Sector	Issued 26 Jun 2023; applies to reporting periods from 1 Jan 2024 (subject to national adoption)
Nature	Voluntary (in many places), oriented toward impact transparency	Moving toward a legal mandate country by country; integrated with financial reporting

Comparison sources: audience & materiality principle per Global Reporting Initiative and IFRS Foundation; issue & effective dates per IFRS Foundation.

The GRI standards structure: read the map before you go

Table 2 — The three families of GRI Standards

Family	Applies to	Main content
Universal Standards (GRI 1, 2, 3 — 2021)	All organisations	GRI 1 Foundation (principles & how to report); GRI 2 General Disclosures (organisational profile, governance); GRI 3 Material Topics (identifying & reporting material topics)
Sector Standards	By specific sector	Sustainability topics specific to a sector (e.g. oil & gas, agriculture, coal…)
Topic Standards	By the material topics selected	Disclosures for each topic (e.g. GRI 305 Emissions, plus water, labour, anti-corruption topics…)

Source: the three-family structure per Global Reporting Initiative — Universal Standards. Standard process: start with GRI 1 & 2, use GRI 3 to select material topics, then report against the relevant Topic/Sector Standards — an SME need not disclose every topic, only those material to it.

Interoperability — good news for SMEs

GRI and the IFRS Foundation signed an MoU in 2022 and, on 24 May 2024, announced a deeper collaboration to deliver full interoperability (IFRS Foundation). For emissions specifically, a January 2024 resource shows GRI 305 and IFRS S2 are highly aligned, both drawing on the GHG Protocol (IFRS Foundation). So a company that has inventoried Scope 1-2-3 under the GHG Protocol does not start over when switching frameworks.

Vietnam's ESG reporting rules

Vietnam has not adopted ISSB into law, but mandatory ESG disclosure for the listed sector already exists. Circular 96/2020/TT-BTC (issued 16 Nov 2020, replacing Circular 155/2015) requires public/listed companies to disclose ESG content — including GHG emissions, energy, water, waste, labour and community — in their annual reports (Keslio). The State Securities Commission has issued GRI-based sustainability reporting guidance since 2015 (GREEN IN Vietnam). Non-listed SMEs are not yet required to file, but any "green" claim already falls under the Law on Protection of Consumer Rights 2023 (No. 19/2023/QH15, effective 1 July 2024), which prohibits false, incomplete or inaccurate information (LuatVietnam).

Table 3 — Legal framework & guidance for ESG reporting in Vietnam

Instrument / guidance	Role	Key points
Circular 96/2020/TT-BTC	Disclosure on the securities market	Issued 16 Nov 2020, replacing Circular 155/2015; public/listed companies disclose ESG (GHG emissions, energy, water, waste, labour, community) in their annual reports — Keslio
SSC's GRI guidance	Orientation for sustainability reporting	The State Securities Commission has provided GRI-based sustainability reporting guidance for listed companies since 2015 — GREEN IN Vietnam
Law on Protection of Consumer Rights 2023 (No. 19/2023/QH15)	Curbs false / misleading information	Issued 20 Jun 2023, effective 1 Jul 2024; prohibits deception or misleading through false, incomplete or inaccurate information about goods/services — LuatVietnam
Advertising Law & Environmental Protection Law 2020	Basis against misleading environmental advertising	Prohibit advertising that misleads on characteristics or effects — applies to every "green" claim

A 5-step ESG reporting roadmap for SMEs

Table 4 — The 5-step roadmap (a general framework, with no sample ESG figures)

Step	What to do	Output
1. Choose the standard & audience	Identify who reads it (customers / investors / EU partners) → choose GRI, ISSB, or both (leveraging interoperability)	A decision on the reporting framework
2. Assess materiality	Use GRI 3 (impact) and/or the ISSB financial lens; consult stakeholders	A list of material topics
3. Collect & measure data	E data (emissions per the GHG Protocol, energy, water, waste), S (labour, safety), G (governance, anti-corruption)	A dataset with sources & methodology
4. Draft the report to standard	Present per GRI Topic Standards / IFRS S1-S2; state scope, period and methodology clearly	A draft ESG report
5. Assure & publish	Review against greenwashing; consider independent assurance; publish (standalone or within the annual report)	A published ESG report

Anti-greenwashing

Every published figure or "green" claim must be measurable, sourced and scope-transparent. Under Vietnamese law (Advertising Law, Consumer Rights Protection Law 2023, Environmental Protection Law 2020), misleading environmental claims are prohibited, and marketing claims must match the numbers in the report. This article therefore gives no specific ESG figures for any sample company — those depend on real activity data and must be measured, computed and sourced by each business.