Most companies are beginning to measure their emissions, and for many, the bulk of those emissions come from the supply chain (Scope 3 – Purchased Goods and Services). Often, more than 80% of a company’s footprint relies on multiplying spend data by industry average emission factors. This approach, while practical, doesn’t reflect actual reductions if suppliers make progress. Essentially, without direct supplier data, net zero or Scope 3 reductions are hard to credibly achieve.

Gathering accurate emissions data from thousands of suppliers can be challenging. Simple forms and calculators won’t cut it—companies must support suppliers in integrating carbon accounting into regular business practices, with audit-ready data so they can rely on this for their own scope 3 reporting. This ensures transparency, rewards progress, and reduces greenwashing risks. Scope 3 data needs the same level of rigour as financial reporting.

Replacing average Scope 3 emissions with actual data requires emissions driven by a supplier’s specific inputs, not generic averages. Companies need to judge the quality of supplier data for replacing an average, a task increasingly managed by finance or external accountants with transparent disclosures. Sumday’s goal is to make quality data accessible and easily shareable, without overwhelming suppliers with endless forms.

Technology alone can’t solve this—it’s also about changing how people engage. Let’s break down the steps, addressing the human challenges that often block progress.

Create a “golden triangle” team from Sustainability, Procurement, and Finance to drive this initiative:

Each team member can access Sumday’s upskilling resources through the Sumday Academy to confidently fulfill their roles.

Instead of one-size-fits-all requests, categorize suppliers into groups:

Tailor Your Communication to each group. Send a clear, context-setting email explaining:

Sumd[AI] helps you prepare these communications with templates to reduce admin for suppliers, making the request manageable and supportive.

Sumday offers templates with best-practice questions, designed to help you replace averages with actuals and track emissions reductions.

When you send a request, suppliers receive:

Customizable Requests: Soon, you’ll be able to customize and save your own templates in Sumday to create tailored requests for different supplier categories.

This isn’t about expecting perfection from suppliers immediately. Instead, tracking engagement alone yields insights that can inform future engagement and highlight high-impact opportunities.

Sumday enables you to monitor which suppliers respond and which don’t, identify those with GHG accounting practices, and better understand supplier barriers to reducing emissions. This data can shape future strategies, whether it’s engaging with major suppliers on reduction plans or creating case studies spotlighting proactive SMBs.

Sumday helps your team identify where supplier data can confidently replace averages. As more suppliers provide data annually, Sumday’s evolving features will streamline this process, making it easy to document and disclose decisions, improving both internal communication and external reporting.

By engaging suppliers thoughtfully and providing:

…you become a valued partner in their sustainability journey. As Scope 3 emissions become increasingly central, this approach may be one of the most impactful steps you can take.

Ready to start? Let’s build a transparent, supportive supply chain and make meaningful progress towards Scope 3 reductions.