# Can you defend your Scope 3 number, one supplier at a time?

Canonical: https://senseible.earth/scope-3-supplier-evidence

When assurance or a customer asks where a Scope 3 Category 1 figure came from, the spend-based estimate is the line that gets challenged. Enter how many suppliers make up about 80% of your purchased-goods spend, how many already send activity data, and how many months you have; the check shows your coverage by supplier count and the monthly pace needed to close the gap.

## Why supplier bills make a figure defensible

The GHG Protocol Scope 3 Technical Guidance ranks Category 1 methods from supplier-specific and hybrid to average-data and spend-based. A supplier’s electricity bills and fuel invoices provide the activity data for the hybrid method, and each line can show its method, emission factor, source and original document.

## Supplier request you can send today

Subject: Energy bills for our Scope 3 reporting Hello, We are measuring the emissions linked to what we buy from you. Instead of a questionnaire, could you share copies of documents you already have, for the last 12 months: 1. Electricity bills for the site that makes our products 2. Fuel invoices (diesel, LPG, PNG, coal or other fuels) 3. Your total production for the same months, in the unit you use PDFs or phone photos are fine. We use them only to calculate the emissions linked to our purchases, and we will share the result with you. Thank you,

## Questions

### Our suppliers are small. Will they actually do this?

They are asked for bills they already keep, not a questionnaire. A PDF or a phone photo of an electricity bill or fuel invoice is enough; Senseible reads it.

### Which GHG Protocol method does this support?

A supplier’s bills give the activity data for the hybrid method in the GHG Protocol Scope 3 Technical Guidance for Category 1. Suppliers without bills stay on average-data or spend-based estimates, labelled as such, so the share of each method is always visible.

### How do supplier documents get into Senseible?

Today, documents are uploaded in Senseible, up to 10 files per batch, and read automatically. Supplier invitations and a supplier portal, intake by email or WhatsApp, and ERP feeds are set up for each enterprise on request.

### Is this an assurance opinion or a compliance certificate?

No. Senseible produces the evidence trail a reviewer looks for: the method, the emission factor and its source, and the original document for each line. Assurance is given by an independent assurance provider.

### How are documents protected?

Each document is fingerprinted with SHA-256 so the same bill cannot be counted twice, and records sit in your organisation’s account. The Trust page sets out how data is handled.

### What does it cost?

The plan on this page is free. Enterprise work is priced to your supplier count and integrations after a short scoping conversation; published plans are on the pricing page.