What Are
Scope 3 Emissions?
Scope 3 emissions represent on average 70–90% of a company's total carbon footprint, yet remain the least frequently quantified. This guide covers all 15 categories, calculation methods applicable to SMEs, and why they become mandatory under CSRD/ESRS E1 from 2025.
What are Scope 3 emissions and why are they difficult to calculate?
Unlike Scope 1 emissions (fuel combustion at owned facilities) and Scope 2 (purchased electricity), Scope 3 emissions occur outside a company's direct operational boundaries. Their calculation is complex because it requires data from hundreds or thousands of suppliers, logistics partners, and customers — entities with their own reporting systems, or none at all. A furniture manufacturer, for instance, must account for emissions from timber harvesting, raw material transport, adhesive and lacquer production, the energy customers use to transport the product home, and ultimately the disposal of the furniture at end of life.
Global studies show that Scope 3 emissions represent 75% of total footprint on average in the industrial sector and over 90% in retail and financial services. Ignoring them amounts to presenting an incomplete and potentially misleading picture of an organisation's real climate impact. For companies with SBTi (Science Based Targets initiative) commitments, Scope 3 reduction is mandatory to align with the 1.5°C pathway.
All 15 Scope 3 Categories — Complete Table
The GHG Protocol organises the 15 categories into upstream emissions (related to procurement) and downstream emissions (related to products sold):
| No. | Category | Direction | Typical Examples |
|---|---|---|---|
| 1 | Purchased goods and services | Upstream | Raw materials, components, packaging |
| 2 | Capital goods | Upstream | Machinery, equipment, office buildings |
| 3 | Fuel & energy-related activities | Upstream | Extraction, refining, transport of fuel |
| 4 | Upstream transport and distribution | Upstream | Delivery of raw materials to factory |
| 5 | Waste generated in operations | Upstream | Production waste sent to landfill/incinerator |
| 6 | Business travel | Upstream | Flights, hotels, trains for employees |
| 7 | Employee commuting | Upstream | Daily home-to-office travel by personal car |
| 8 | Upstream leased assets | Upstream | Warehouses or equipment leased from third parties |
| 9 | Downstream transport and distribution | Downstream | Delivery of finished products to customers |
| 10 | Processing of sold products | Downstream | Intermediate products requiring further processing |
| 11 | Use of sold products | Downstream | Energy consumed by sold appliances and vehicles |
| 12 | End-of-life treatment of sold products | Downstream | Recycling, landfill after consumer use |
| 13 | Downstream leased assets | Downstream | Real estate leased to tenants |
| 14 | Franchises | Downstream | Emissions from franchisees under the parent brand |
| 15 | Investments | Downstream | Investment portfolio, loans extended by banks |
Why is Scope 3 becoming mandatory in Romania?
The CSRD Directive (Corporate Sustainability Reporting Directive) requires Scope 3 reporting under the ESRS E1 — Climate Change standard, phased in as follows: companies with more than 500 employees from financial year 2024; large companies (>250 employees or >€40M turnover or >€20M total assets) from 2025; and listed SMEs from 2026. An estimated 500 Romanian companies are affected in the first wave and over 3,000 in subsequent phases.
Beyond legal obligations, market pressures are accelerating adoption. Major European retailers (IKEA, Kaufland, Tesco, Metro) are requesting Romanian suppliers to complete sustainability questionnaires that include Scope 3 data. Companies unable to provide this data risk losing contracts to better-prepared competitors. Banks and European investment funds also apply ESG criteria when granting financing, and the absence of reporting increases perceived risk.
How to calculate Scope 3 without exact supplier data?
Collecting primary data from all suppliers is ideal, but impossible at the outset. The GHG Protocol recognises three main methods depending on data availability:
Spend-Based Method
Multiply financial expenditure (EUR) by an economic emission factor (kg CO₂e/EUR) specific to the spending category. Advantage: requires only accounting data. Disadvantage: low precision (±50%). Recommended as a starting point for Cat. 1.
Average-Data Method
Multiply physical quantities (kg, tonnes, km) by average emission factors from databases (DEFRA, Ecoinvent, EXIOBASE). Medium precision (±30%). Recommended for SMEs with procurement data available.
Supplier-Specific Method
Use actual data communicated by suppliers (declared CFP, EPD, verified LCA). High precision (±10%). Required for advanced CSRD reporting and SBTi commitments.
Practical steps for your first Scope 3 calculation
- Define the organisational boundary — Operational scope (operational control or financial control?) and which subsidiaries to include.
- Identify relevant categories — Not all 15 are material for every company. Use a materiality assessment: a quick spend-based estimate to prioritise the top 3–5 categories.
- Collect activity data — Procurement invoices (Cat. 1), transport reports (Cat. 4, 9), expense reports (Cat. 6), HR data for commuting (Cat. 7).
- Choose emission factors — DEFRA Conversion Factors (UK DESNZ, updated annually), Ecoinvent 3.x, or EXIOBASE for the spend-based method.
- Calculate, document and verify — Use a spreadsheet or software platform. Document all assumptions and uncertainties.
- Set a base year and report — Per ESRS E1, declare a baseline, the chosen methodology, boundaries and data. CarbonDRI guides you step by step through this process.
To calculate your Scope 2 electricity emissions as a concrete first step, use our free Scope 2 calculator. For a full Scope 1+2+3 calculation conforming to ESRS E1, contact the CarbonDRI team.
Frequently asked questions about Scope 3
Am I required to report all 15 Scope 3 categories?
No. ESRS E1 requires reporting material categories — those that exceed a significance threshold relative to total emissions. In practice, for a Romanian manufacturing company, categories 1 (purchased goods), 4 (upstream transport), 9 (downstream transport) and 11 (use of sold products) typically account for 80%+ of Scope 3. You must still justify why the other categories are not material.
How precise do Scope 3 data need to be for CSRD reporting?
ESRS E1 does not impose a specific numerical precision, but requires transparency on methods used and associated uncertainties. Companies using the spend-based method must state this and describe a data-quality improvement plan over time. The sustainability report must be audited by an accredited third party.
How do I obtain emission data from my suppliers?
Send a questionnaire to your main suppliers (top 10–20 by procurement value) requesting the carbon footprint of delivered products/services. You can use the CDP Supply Chain format or the EcoVadis platform. If a supplier cannot respond, use the average-data method as a fallback. CarbonDRI can prepare the questionnaire in Romanian, English and German.
What is the link between Scope 3 and CBAM?
CBAM (Carbon Border Adjustment Mechanism) targets embedded carbon in products imported from outside the EU — essentially the Scope 1 of the producer in the third country. If you import steel, aluminium or cement, your Scope 3 Cat. 1 data overlaps with CBAM obligations. Read our full CBAM Romania guide.
How much does a complete Scope 3 calculation cost?
The price varies by supply chain complexity, number of material categories and level of detail required. A screening calculation (spend-based, all categories) for an SME with 50–200 employees generally costs €2,000–5,000. A full calculation with supplier data, prepared for CSRD audit, can reach €8,000–20,000. Contact CarbonDRI for a personalised quote.
Calculate Your Company's Scope 3
CarbonDRI offers Scope 3 assessments in line with GHG Protocol and ESRS E1, with audit-ready reports. Our services cover all 15 categories with documented methodology and up-to-date emission factors.
Request a Scope 3 Assessment →See also: Life Cycle Assessment (LCA) · Carbon Footprint Product (CFP) · CSRD & ESG Guide