UK SRS Implementation
UK SRS Scope 3 Emissions Reporting: Complete Practitioner Guide
How to build a UK SRS S2-compliant Scope 3 inventory covering all 15 GHG Protocol categories, implementing the data quality hierarchy, calculating financed emissions, and preparing for limited assurance requirements.
| Category | Description | Typical Data Sources |
|---|---|---|
| Cat 1: Purchased Goods | Raw materials, components, products | Supplier data, spend-based calculations |
| Cat 2: Capital Goods | Equipment, machinery, buildings | Capital expenditure, asset registers |
| Cat 3: Energy Activities | Fuel, electricity not in S1/S2 | Energy bills, transmission losses |
| Cat 4: Transportation | Upstream transport, distribution | Logistics providers, freight data |
| Cat 5: Waste | Treatment of operational waste | Waste contractors, disposal methods |
| Cat 6: Business Travel | Employee travel for business | Travel booking systems, expense claims |
| Cat 7: Commuting | Employee daily commuting | Employee surveys, office locations |
| Cat 8: Leased Assets | Upstream leased assets | Lease agreements, property data |
| Cat 9: Downstream Transport | Distribution of sold products | Customer delivery, logistics |
| Cat 10: Processing | Processing of sold products | Customer operations, product use |
| Cat 11: Use of Products | End-user operation of products | Product specifications, usage patterns |
| Cat 12: End-of-Life | Disposal of sold products | Product lifecycle, disposal methods |
| Cat 13: Leased Assets | Downstream leased assets | Tenant operations, subletting |
| Cat 14: Franchises | Franchise operations | Franchisee reporting, operational data |
| Cat 15: Investments | Investment portfolio emissions | PCAF methodology, portfolio holdings |
How does UK SRS S2 differ from existing TCFD Scope 3 requirements?
UK SRS S2 mandates disclosure of all 15 GHG Protocol categories where material, requires specific data quality disclosures, and introduces the PCAF methodology for financed emissions (Category 15). TCFD requirements were more flexible on Scope 3 categories and methodology.
What is the data quality hierarchy required under UK SRS S2?
UK SRS S2 requires a five-tier data quality hierarchy: (1) Supplier-specific data, (2) Secondary data from similar companies, (3) Regional/country averages, (4) Global averages, (5) Proxy data. Companies must disclose the percentage of emissions calculated at each level and improvement plans to move up the hierarchy.
How should financial institutions calculate Category 15 (Investments) emissions?
Financial institutions must use the PCAF (Partnership for Carbon Accounting Financials) methodology for Category 15. This includes the PCAF data quality score (1-5), covers all six asset classes (listed equity, corporate bonds, business loans, project finance, commercial real estate, mortgages), and requires disclosure of financed emissions intensity metrics.
What materiality threshold applies to Scope 3 categories?
UK SRS S2 does not set a fixed materiality threshold. Companies must determine materiality based on quantitative significance (typically >1% of total emissions) and qualitative factors (value chain influence, stakeholder expectations, business model relevance). The materiality assessment process and criteria must be disclosed.
When will Scope 3 assurance become mandatory?
Limited assurance on Scope 3 emissions is proposed to become mandatory from January 2028 under the FCA timeline. This will follow ISSA (UK) 5000 sustainability assurance standards, focusing on material categories and data quality disclosure. Companies should begin assurance readiness preparations immediately.
How can companies improve their Scope 3 data quality?
Improvement strategies include: (1) Direct supplier engagement programmes, (2) Contract clauses requiring emissions data, (3) Industry collaboration initiatives, (4) Technology platforms for data collection, (5) Third-party verification programmes. Companies must disclose specific improvement plans with timelines in their UK SRS S2 reports.
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