What Are Scope 1, 2, and 3 Emissions? A Complete Guide

Learn the essentials of scope emissions, and stay ahead of the curve when it comes to consumer and investor expectations, and evolving regulation.

Aidan Gil
March 2, 2026
Two tall, industrial concrete smokestacks with stand against a clear blue sky, partially obscured by thick plumes of white steam

In the world of sustainability, "carbon footprint" is no longer a vague buzzword. To be taken seriously by investors, regulators, and customers, companies must categorize their environmental impact into three distinct categories: Scope 1, 2, and 3.

Developed by the Greenhouse Gas (GHG) Protocol, these tiers help organizations understand exactly where their emissions are coming from, and who is ultimately responsible for them. 

So, what exactly are Scope 1, 2 and 3 emissions? Here’s a quick breakdown on the concepts and best practices to make sure your company saves money, and doesn’t fall behind the expectations of consumers, investors, suppliers, or regulation.

Scope 1: Direct Emissions (The Stuff You Own)

Scope 1 covers emissions from sources that an organization owns or controls directly. If your company burns fuel or leaks gas on-site, it’s Scope 1.

  • Stationary Combustion: Boilers, furnaces, or heaters fueled by natural gas or oil.
  • Mobile Combustion: Fuel used by company-owned cars, vans, or trucks.
  • Fugitive Emissions: Leaks of greenhouse gases (like refrigerants from AC units).
  • Process Emissions: CO2 released during industrial manufacturing (e.g., cement production).

Real-World Example: A delivery company’s Scope 1 includes the diesel burned by its own fleet of trucks.

Scope 2: Indirect Emissions (The Energy You Buy)

Scope 2 covers emissions from the generation of purchased energy. While the emissions physically happen at a power plant, they are "yours" because you bought the energy to run your operations.

  • Purchased electricity.
  • Purchased steam, heating, or cooling. 

Real-World Example: An office building’s Scope 2 includes the emissions created by the local utility plant to keep the lights and servers running.

If you’d like additional information on identifying and tracking scope 1 and 2 emissions, check out the EPA’s Scope 1 and Scope 2 Inventory Guidance page.

Scope 3: Value Chain Emissions (The Everything Else)

Scope 3 is the heavy hitter. It includes all other indirect emissions that occur in a company’s supply chain, both upstream and downstream. For most companies, Scope 3 accounts for over 70% of their total footprint.

The GHG Protocol divides Scope 3 into 15 categories, mainly including:

  • Upstream: Purchased goods and services, business travel, and employee commuting.
  • Downstream: The use of sold products (e.g., the electricity a toaster uses in a customer’s home) and the end-of-life treatment of products.

Real-World Example: For an iPhone, Scope 3 includes the mining of raw materials (upstream) and the electricity used by the customer to charge the phone (downstream).

Why Reporting Beyond Scope 1 and 2 is Mandatory

Historically, companies only focused on Scopes 1 and 2 because they are easier to measure. However, reporting on Scope 3 is becoming the new standard for three reasons:

1. Risk Management: Supply chain disruptions are often linked to climate change.

2. Investor Demand: ESG (Environmental, Social, and Governance) funds now require full transparency to assess a company’s long-term viability.

3. Regulation: New laws, such as California’s SB 253 and the EU’s CSRD, are making Scope 3 reporting a legal requirement for many.

Which Scopes Matter Most for Mid-Market Companies?

While enterprise giants have the resources to track everything, mid-market companies often struggle with the complexity of Scope 3. However, Scope 3 is often where the most significant cost savings live. By identifying hotspots in the supply chain, mid-market firms can negotiate better with suppliers or switch to more efficient logistics, directly impacting their bottom line and their green credentials.

Additionally, Full-scope accounting (tracking Scopes 1, 2, and 3) is a strategic asset that builds trust across your entire business ecosystem. Here’s how it benefits your three primary stakeholders:

1. For Investors: De-Risking the Portfolio

Investors view carbon as a proxy for management quality and long-term viability.

2. For Consumers: Building Brand Integrity

Today’s consumers are increasingly wary of greenwashing. They don't just want to know that your office has LED lights; they want to know the true cost of the products they buy.

  • Radical Transparency: Providing data on the entire lifecycle of a product (upstream and downstream) builds deep brand loyalty and justifies premium pricing for sustainable goods.
  • Empowered Choice: When a company reports Scope 3, it allows consumers to see the impact of their own usage and disposal, making them partners in the sustainability journey rather than just targets of a marketing campaign.

3. For Suppliers: Driving Innovation and Stability

In full-scope accounting, your Scope 3 is your supplier's Scope 1. This creates a shared language for improvement.

  • Operational Efficiency: When you ask a supplier for their carbon data, it often reveals inefficiencies in their manufacturing or logistics. Solving these together usually leads to lower costs and shorter lead times.
  • Preferred Partnerships: Suppliers who can provide accurate carbon data become "sticky." They move from being a replaceable vendor to a strategic partner that helps the lead company meet its science-based targets.

From Compliance to Competitive Advantage

Categorizing your emissions into Scopes 1, 2, and 3 is no longer just a regulatory hurdle, it is a foundational business strategy. While Scopes 1 and 2 provide a clear view of your direct operational impact, Scope 3 is the true heavy hitter, so to speak, and is often representing over 70% of your total carbon footprint.

By adopting full-scope accounting, companies move beyond simple measurement to active value creation:

  • Investors gain a de-risked portfolio and a clear proxy for highquality management.
  • Consumers receive the radical transparency they demand, building long-term brand integrity and loyalty.
  • Suppliers become strategic partners in innovation, uncovering operational efficiencies that lower costs for everyone involved.

The era of manual spreadsheets is over; accuracy now requires digital tools and proactive supplier engagement. Whether you are setting your base year or preparing for legal requirements like California’s SB 253 or the EU’s CSRD, the time to build your carbon accounting infrastructure is now.

Don't wait for a regulatory shock to find your hotspots. Start with your utility bills, engage your value chain, and turn your sustainability data into your most valuable strategic asset.

FAQs

What is the main difference between the three Scopes?

  • Scope 1 are direct emissions from sources you own (like company vehicles).
  • Scope 2 are indirect emissions from energy you purchase, like electricity.
  • Scope 3 covers all other indirect emissions in your entire value chain, from raw materials to customer use.

Is Scope 3 reporting actually mandatory?

  • Yes, new regulations like California’s SB 253 and the EU’s CSRD are making Scope 3 a legal requirement for many businesses.
  • Many investors and enterprise customers now require this data to assess long-term risk.

Does Scope 3 lead to 'double counting' of emissions?

  • No. While one company’s Scope 3 is another’s Scope 1, tracking both ensures every gram of COis accounted for by someone in the chain.

How can a mid-market company measure Scope 3 if they don't have perfect data?

  • You don't need a meter on every factory. You can use spend-based modeling or average-data methods to create highly accurate estimates.

Where should a business start with carbon accounting?

  • Start by setting a base year and gathering l like utility bills (Scope 2) and fuel receipts (Scope 1).
  • Engage your top 10 suppliers early to begin the Scope 3 data collection process.
Aidan Gil
March 2, 2026

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