Why Scope 3 is where CDP scores are won or lost
For most companies, Scope 1 and Scope 2 emissions are the smaller part of the picture. The GHG Protocol estimates that across global supply chains, Scope 3 typically represents 70 to 90 percent of a company’s total footprint. In agri food, retail, financial services, and consumer goods, the share is often above 95 percent.
Yet Scope 3 is the section where most CDP responses fall short. Companies that submit complete Scope 1 and 2 inventories routinely report only three or four Scope 3 categories, with spend based estimates and limited methodology. CDP scoring penalises this gap heavily. A C to B transition almost always passes through stronger Scope 3 coverage.
This article maps the 15 Scope 3 categories, explains which ones to prioritise, what scorers expect at each level, and how to move from spend based estimates to activity based data without overwhelming the team.
The 15 Scope 3 categories
GHG Protocol defines 15 Scope 3 categories, split into upstream and downstream:
Upstream categories
- 1. Purchased goods and services: emissions embedded in the goods and services your company buys. Almost always the largest single category.
- 2. Capital goods: emissions from the production of long lived assets (buildings, machinery, vehicles).
- 3. Fuel and energy related activities: emissions not already in Scope 1 or 2 (transmission losses, well to tank for fuels).
- 4. Upstream transportation and distribution: third party logistics for inbound goods.
- 5. Waste generated in operations: disposal and treatment of waste.
- 6. Business travel: flights, trains, hotels, rental cars.
- 7. Employee commuting: home to work travel.
- 8. Upstream leased assets: emissions from assets your company leases as a lessee.
Downstream categories
- 9. Downstream transportation and distribution: outbound logistics.
- 10. Processing of sold products: emissions from third parties processing intermediate goods.
- 11. Use of sold products: emissions during product use phase. Major for energy using products.
- 12. End of life of sold products: disposal of products after consumer use.
- 13. Downstream leased assets: emissions from assets your company leases out.
- 14. Franchises: emissions from operations of franchisees.
- 15. Investments: emissions financed through investments. Material for financial institutions.
Not every category is material for every company. CDP requires a screening exercise to identify which ones are.
Which categories to prioritise
A common mistake is trying to cover all 15 categories with poor data instead of focusing on the material ones with good data. The materiality screening is the first step of any Scope 3 programme.
For most non financial sectors, four categories tend to dominate:
- Category 1 (purchased goods and services) typically represents 50 to 80 percent of Scope 3 in retail, consumer goods, and industrial sectors.
- Category 4 (upstream transportation) is significant in any sector with physical supply chains.
- Category 11 (use of sold products) dominates in automotive, energy, and electronics, often above 50 percent of total Scope 3.
- Category 15 (investments) dominates in banking and insurance, often above 95 percent of Scope 3.
Start with the categories that drive 80 percent of the footprint. Cover the long tail later. A complete inventory of three material categories scores better than a partial inventory of all 15.
Spend based vs activity based data
CDP recognises three primary methods for Scope 3 quantification, each with different scoring impact:
Spend based: emissions calculated from financial spend multiplied by an emission factor (kg CO2e per EUR). Easy to start with because spend data exists in any ERP. Acceptable in year one, but penalised in year three if the company has not transitioned to activity data for material categories.
Hybrid: a mix of spend based for tail suppliers and activity based for top suppliers. The most realistic approach for many companies.
Activity based: emissions calculated from physical activity data (kg of steel, km of trucking, MWh of customer use) multiplied by emission factors specific to the activity. This is what scorers reward most strongly.
The progression from spend to activity is the central narrative of any multi year Scope 3 programme. CDP rewards companies that show a clear plan and progress, not just the current state.
What scorers expect at each band
To reach the C band, CDP requires:
- Screening of all 15 categories with documented exclusions.
- Quantitative reporting of at least the most material categories.
- Some methodology documentation.
To reach B:
- Documented inventory of all material categories, with methodology per category.
- A credible plan to move from spend to activity for the largest categories.
- Coverage of value chain emissions in risk assessments and target setting.
To reach A:
- Complete Scope 3 inventory across all material categories with activity based methodology dominating.
- Limited assurance over material Scope 3 categories.
- Supplier engagement programme with measurable outcomes.
- Scope 3 included in Science Based Targets initiative validated targets.
- Sector specific methodology where applicable (e.g., FLAG for food and agriculture).
How to start a Scope 3 programme
The most effective approach we have seen is structured in three phases.
Phase 1: screening and baseline (3 to 4 months)
Identify the categories that apply to your business. For each, run a high level estimate using spend or industry averages. The output is a Pareto chart showing which categories drive the bulk of emissions.
This phase produces the first quantitative Scope 3 number, which is enough to score in the C band.
Phase 2: methodology and primary data for top categories (6 to 12 months)
For the categories that drive 80 percent of emissions, replace spend based estimates with activity based methodology. This typically means:
- For purchased goods and services: collect supplier specific emission factors for the top 20 to 50 suppliers, using their CDP responses, life cycle assessments, or supplier surveys.
- For upstream transportation: pull tonne kilometres and mode from logistics providers, apply GLEC or DEFRA factors.
- For business travel: connect to the corporate travel agency feed and apply DEFRA or ICAO factors.
- For employee commuting: run an annual employee survey and model average distances and modes.
This phase produces a defensible inventory that scores in B band and lays the foundation for verification.
Phase 3: maturity and engagement (12 to 24 months)
Extend activity based coverage to the long tail. Engage suppliers to set their own SBTi targets. Add limited assurance over material categories. Integrate Scope 3 into product level life cycle assessment where customer requests demand it.
This phase moves the score to B plus or A.
Common pitfalls
Across hundreds of Scope 3 inventories, the same gaps repeat:
- Skipping the screening exercise. Without screening, companies either over invest in immaterial categories or skip material ones.
- Spend based on top suppliers. Using spend based factors for suppliers that already provide activity data is a missed opportunity for scoring credit.
- Ignoring use of sold products. For manufacturers of energy using equipment, this is the single largest category. Skipping it is a structural inventory weakness that scorers flag.
- Not connecting Scope 3 to targets. SBTi and CDP both reward Scope 3 inclusion in target setting. A complete inventory without a target loses easy scoring credit.
- Reporting one year and not the next. Continuity scores. Year on year comparability is part of CDP scoring.
Where Dcycle fits
Scope 3 data lives in many places: ERP for spend, logistics platforms for transport, travel tools for business travel, supplier portals for primary data, and product life cycle assessment systems for use phase. Dcycle connects all of these and structures the output in the 15 GHG Protocol categories CDP scoring uses. Companies typically reduce Scope 3 data collection time by 60 to 80 percent and discover gaps that previous spreadsheet driven processes missed entirely.
To see how this would apply to your sector, request a demo. For broader context on how Scope 3 fits with CSRD and SBTi, the resource hub covers the full picture.
Final thought
Scope 3 is no longer optional. The combination of CDP scoring, SBTi requirements, CSRD disclosure, and customer questionnaires has made comprehensive Scope 3 reporting a baseline expectation, not a leadership move. Companies that build the data architecture once, then improve it year over year, are the ones whose disclosures will hold up to scrutiny in 2028 and beyond.