ESG Reporting Documentation: How to Review Sustainability Reports for Accuracy and Compliance
ESG reporting is becoming mandatory globally. Here's how to review sustainability reports for accuracy, consistency, and compliance — covering GRI, ISSB, CSRD, and common quality issues.
ESG reporting has shifted from voluntary storytelling to mandatory disclosure. The EU's CSRD requires approximately 50,000 companies to report under European Sustainability Reporting Standards. The ISSB's IFRS S1 and S2 are being adopted by jurisdictions globally. The SEC's climate disclosure rules affect US-listed companies. This isn't optional communications anymore — it's regulated reporting with assurance requirements.
The problem: most ESG reports are written by sustainability teams or communications departments, not financial reporting teams. The rigour, accuracy standards, and review processes that apply to financial statements often don't apply to sustainability reports — yet regulators are beginning to require the same level of assurance.
ESG Reporting Frameworks
| Framework | Scope | Who Uses It | Status |
|---|---|---|---|
| GRI (Global Reporting Initiative) | Comprehensive sustainability (all ESG topics) | 10,000+ organisations globally | Voluntary (most widely used) |
| ISSB (IFRS S1 & S2) | Investor-focused sustainability and climate | Being adopted by 20+ jurisdictions | Mandatory where adopted |
| ESRS (European Sustainability Reporting Standards) | Comprehensive, double materiality | EU companies under CSRD | Mandatory (phased from 2024) |
| SASB | Industry-specific material topics | US-focused, now consolidated under ISSB | Consolidated into ISSB |
| TCFD | Climate-related financial disclosures | Global — governance, strategy, risk management, metrics | Superseded by ISSB S2 in many jurisdictions |
| CDP | Climate, water, forests questionnaires | 23,000+ companies respond | Voluntary (investor/customer pressure) |
Most organisations report against multiple frameworks. The convergence toward ISSB is reducing this complexity, but for now, multi-framework reporting is the norm.
What ESG Reports Must Include
Common Disclosure Requirements Across Frameworks
| Category | What to Disclose |
|---|---|
| Governance | Board oversight of sustainability matters, management's role, sustainability governance structure |
| Strategy | Sustainability-related risks and opportunities, impact on business model, strategy resilience |
| Risk management | How sustainability risks are identified, assessed, and managed; integration with enterprise risk management |
| Metrics and targets | Quantitative performance data, targets, progress against targets |
| GHG emissions | Scope 1 (direct), Scope 2 (energy indirect), Scope 3 (value chain) emissions |
| Materiality assessment | How material topics were identified, stakeholder engagement process |
| Policies | Sustainability policies, due diligence processes |
| Actions | Specific actions taken and planned, resource allocation |
CSRD/ESRS-Specific Requirements
The EU's CSRD introduces requirements that go beyond other frameworks:
| Requirement | What It Means |
|---|---|
| Double materiality | Report on both how sustainability matters affect the company AND how the company affects society/environment |
| Value chain reporting | Disclosures must cover the entire value chain, not just own operations |
| Forward-looking information | Targets, transition plans, and financial effects of sustainability matters |
| Digital tagging | Reports must be digitally tagged (XBRL) for machine readability |
| Limited assurance | Third-party assurance required (moving to reasonable assurance over time) |
Common ESG Report Quality Issues
Issue 1: Greenwashing Language
Vague, positive language without substantiation. Regulators and rating agencies are increasingly flagging unsubstantiated claims.
| Greenwashing | Substantiated |
|---|---|
| "We are committed to sustainability" | "We reduced Scope 1 emissions by 12% in 2025 against a 2020 baseline, tracking to our 2030 target of 42% reduction" |
| "We have made significant progress" | "We achieved 3 of 5 sustainability targets: renewable energy (78% vs 75% target), waste diversion (82% vs 80%), water intensity (reduced 8% vs 5% target). Two targets were missed: Scope 3 emissions (reduced 3% vs 5% target) and supplier audits (72% vs 80% target)" |
| "Our products are eco-friendly" | "Product X uses 34% recycled materials by weight, verified by [certifier], compared to 15% industry average (source: [industry report])" |
Issue 2: Inconsistent Data
GHG emissions reported in the ESG report don't match emissions in the CDP response. Revenue figures in the sustainability report don't match the annual report. Inconsistency undermines credibility and triggers auditor/assurance queries.
Prevention: Establish a single data source for each metric. Cross-reference all published figures before finalising any report.
Issue 3: Missing Methodology
Data without methodology is unverifiable. If you report "Scope 2 emissions: 12,450 tCO2e," the reader needs to know: market-based or location-based? Which emission factors? Which organisational boundary? What's included/excluded?
Issue 4: Cherry-Picking Metrics
Reporting only favourable metrics while omitting unfavourable ones. If your water consumption increased 15% but your energy consumption decreased 8%, reporting only the energy improvement is misleading.
Issue 5: Missing Targets and Progress
Metrics without targets lack context. "We emitted 50,000 tCO2e" means nothing without: what was the target? What was last year's figure? Is this on track for the long-term goal?
Issue 6: Disconnect Between Narrative and Data
The narrative section claims strong sustainability performance while the data shows flat or declining metrics. This disconnect is immediately visible to analysts and assurance providers.
Reviewing ESG Reports
Accuracy Review Criteria
| Criterion | Weight | What to Check |
|---|---|---|
| Data accuracy | 3 | Numbers match source data, calculations verified, units consistent |
| Methodology transparency | 3 | Emission factors, boundaries, calculation methods disclosed |
| Internal consistency | 3 | Figures consistent across all sections of the report and across all published reports |
| External consistency | 2 | Figures align with annual report, CDP response, and regulatory filings |
| Completeness | 2 | All material topics covered, no cherry-picking of favourable metrics |
Compliance Review Criteria
| Criterion | Weight | What to Check |
|---|---|---|
| Framework alignment | 3 | All required disclosures for the chosen framework(s) present |
| Materiality coverage | 3 | Material topics identified and reported (per the applicable materiality standard) |
| Target disclosure | 2 | Targets set for material metrics, progress reported, methodology for target-setting disclosed |
| Governance disclosure | 2 | Board oversight, management responsibility, governance structure documented |
| Assurance readiness | 2 | Data trails exist, methodology documented, sources referenced — ready for third-party verification |
Quality Review Criteria
| Criterion | Weight | What to Check |
|---|---|---|
| Substantiation | 3 | Every claim supported by specific data or evidence; no unsubstantiated assertions |
| Balance | 2 | Both achievements and challenges/missed targets reported |
| Readability | 2 | Accessible to target audience (investors, stakeholders), not buried in jargon |
| Narrative-data alignment | 2 | Narrative claims supported by the data presented |
| Comparability | 1 | Year-on-year data presented, restated if methodology changed |
ESG Report Review Process
| Stage | Who | What They Review |
|---|---|---|
| Data verification | Data owners / Sustainability team | Source data accuracy, calculation verification |
| Methodology review | Technical specialist / External consultant | Emission factor selection, boundary definitions, methodology compliance |
| Compliance review | Sustainability team / Legal | Framework alignment, regulatory compliance, disclosure completeness |
| Quality review | Communications / Content quality team | Readability, substantiation, balance, narrative-data alignment |
| Executive review | CFO / CSO / Board committee | Strategic alignment, risk assessment, sign-off |
| External assurance | Assurance provider | Limited or reasonable assurance per the applicable standard |
Frequently Asked Questions
Which framework should we report against?
Follow your regulatory requirements first (CSRD/ESRS if EU-regulated, ISSB if your jurisdiction adopts it). Beyond compliance, GRI remains the most comprehensive voluntary framework. If investors are your primary audience, ISSB is the priority. Many organisations report against multiple frameworks using a mapping approach.
Do we need third-party assurance?
CSRD requires limited assurance (moving to reasonable assurance). Other jurisdictions are moving in this direction. Even where not required, voluntary assurance increases credibility with investors and rating agencies. Start with limited assurance on GHG emissions — the most scrutinised metric.
How do we handle Scope 3 emissions?
Scope 3 is the most challenging category — it covers value chain emissions outside your direct control. Start with the most material Scope 3 categories for your industry (typically purchased goods and services, use of sold products, or employee commuting). Use the GHG Protocol Scope 3 Standard for methodology. Acknowledge estimation uncertainty transparently.
What's double materiality?
CSRD/ESRS requires double materiality: report on topics that are material from BOTH perspectives — (1) how sustainability matters create financial risks/opportunities for the company (financial materiality / "outside-in") AND (2) how the company impacts people and the environment (impact materiality / "inside-out"). This is broader than ISSB, which focuses primarily on financial materiality.
Can AI review help with ESG reports?
AI review can check: claim substantiation (are assertions supported by data?), internal consistency (do figures match across sections?), disclosure completeness (are all required framework elements present?), readability, and greenwashing indicators (vague language without specific evidence). It cannot verify data accuracy against source systems or assess the appropriateness of methodological choices.
Key Takeaways
- ESG reporting is becoming mandatory — CSRD, ISSB, and SEC rules are transforming voluntary disclosure into regulated reporting.
- Common quality issues: greenwashing language, inconsistent data, missing methodology, cherry-picked metrics, and narrative-data disconnect.
- Review for accuracy, compliance, AND quality — ESG reports need the same rigour as financial reporting.
- Substantiate every claim — vague sustainability language is a regulatory and reputational risk.
- Establish single data sources for each metric and cross-reference across all published reports.
- Prepare for assurance — document methodology and maintain data trails from the start.
- AI review checks substantiation, consistency, completeness, and readability — data accuracy and methodology require specialist verification.
This article is for informational purposes only. ESG reporting requirements vary by jurisdiction, framework, and company type. Consult a qualified sustainability reporting specialist or assurance provider for guidance specific to your organisation and reporting obligations.