Supplier-specific emission factors: how they strengthen your Scope 3 reporting

At the same time, expectations for data accuracy are shifting from estimated averages to verifiable, supplier-level information. Understanding and applying supplier-specific emission factors has become an essential step toward accurate disclosure, credible performance tracking, and informed decision-making.

Why Scope 3 accuracy matters

Scope 3 emissions often account for the majority of a company’s carbon footprint, yet they are typically the least precise. Due to the scale of emissions that need to be calculated in this category, many organisations still rely on industry-average emission factors, which only offer a broad estimate of supply chain impact.

This approach can satisfy reporting requirements due to the conditions set by limited assurance, but provides far less insight into real decarbonization performance. To improve accuracy, companies are increasingly using supplier-specific emission factors, data that reflects how individual suppliers operate.

What supplier-specific emission factors are

Supplier-specific emission factors are greenhouse gas (GHG) values calculated from a supplier’s own operations, energy use, and production processes. They provide more accurate Scope 3 emissions data than general averages taken from lifecycle databases.

Generic data describes what an average supplier might emit, while supplier-specific data shows what a company’s actual suppliers emit. This replaces assumption-based reporting with data based on estimated performance.

It does go without saying though, that there is a nuance here. Specifically, that poor data is poor data, regardless of its source. It may be true that when calculated using robust and consistent methodologies, supplier-specific emission factors can significantly improve accuracy compared to generic averages. However, poorly documented supplier data can introduce new uncertainty.

Keep that in mind while reading this article and ensure that in your own due diligence, you use the same rigor of quality assurance for supplier-specific data, as you do your own.

Why supplier-specific data improves Scope 3 emissions reporting

Higher accuracy and transparency

Supplier-specific emission factors capture the real carbon intensity of purchased goods and services. Using verified supplier data reduces uncertainty, supports consistent calculation, and lowers the risk of overstating progress or misrepresenting impact.

Audit-ready and regulation-aligned

Under frameworks such as ESRS E1, companies must disclose how much of their Scope 3 data comes from primary rather than secondary sources. Supplier-specific emission factors qualify as high-quality primary data, which aligns with audit and assurance expectations in sustainability statements.*

*Note: Supplier-based emissions factors qualify as primary data when they are based on the supplier’s own operational and emissions data rather than generic databases

Sharper insights for supplier engagement

Supplier-level data enables companies to identify which suppliers contribute most to emissions and to target engagement accordingly. It supports structured discussions about operational improvements, energy sourcing, and material choices.

The financial advantages of supplier-specific Scope 3 data

Cost control and carbon pricing readiness

Supplier-specific data helps identify carbon-intensive inputs and prepare for carbon pricing, border adjustments, and emissions trading costs. Using verified supplier data ensures that reported emissions and associated costs reflect real conditions, improving cost forecasting and exposure management.

Investor confidence and access to capital

Verified Scope 3 emissions data strengthens ESG credibility, credit ratings, and eligibility for sustainable finance instruments. Investors value transparency in emissions accounting, and supplier-level data reduces uncertainty in transition and risk assessments.

What’s more, supplier-specific emissions factors are key for better transition plans as investors need credible decarbonization pathways and SE data shows whether reductions come from real value-chain change

Procurement leverage and competitive differentiation

Understanding actual supplier emission factors provides a data-based basis for procurement decisions. It allows for the integration of emissions performance into supplier evaluation criteria and supports product differentiation based on verified environmental performance.

AKA, your suppliers’ real emissions help you make purchasing decisions based on facts, not estimates. It means you can compare suppliers not just on price or quality, but also on how climate-friendly they are. This lets you choose lower-emission suppliers and prove that your products are made with verified, environmentally responsible partners.

How to transition from generic to supplier-specific emission factors

1. Prioritize material categories: Begin with suppliers and categories that represent the largest share of Scope 3 emissions, such as purchased goods, logistics, or capital goods.
   
2. Request and standardize data: Ask suppliers to share emissions data aligned with recognised standards such as the GHG Protocol or ISO 14064. Use consistent templates to ensure comparability.
   
3. Verify and integrate: Where possible, validate supplier data through third-party assurance and link it directly to internal sustainability systems or reporting frameworks.
   
4. Collaborate and reward transparency: Encourage suppliers to measure and disclose their emissions by providing resources, clear expectations, and feedback. Transparency can be integrated into supplier evaluation and contract renewal processes.

Turning compliance into competitive advantage

Adopting supplier-specific emission factors improves data quality, reduces compliance risk, and supports effective climate strategy.

By improving the accuracy of Scope 3 emissions reporting, organizations can:

1. Reduce greenwashing and audit risk
2. Gain reliable insight into supplier performance
3. Prepare for evolving regulatory and carbon cost frameworks
4. Strengthen investor confidence and external reporting credibility

As sustainability data increasingly overlaps with financial data, supplier-specific emission factors offer a measurable way to improve accuracy, traceability, and strategic decision-making.

How Position Green supports supplier-specific data management

Position Green enables companies to collect, manage, and verify supplier-specific data to improve the quality of Scope 3 reporting. Through our dedicated Supplier Assessment and traceable data workflows, this approach strengthens compliance readiness and supplements a robust decarbonization strategy for you and your suppliers.

If you would like to see firsthand how the software makes engaging your suppliers and auditing your supply chain faster and more expedient, we’d be happy to show you over a brief call.