Scope 3 emissions are the greenhouse gases a company does not produce itself, but causes others to produce on its behalf

When a company reports its carbon footprint, it counts three types of emissions. Scope 1 is what the company burns directly — fuel in its own trucks, gas for its own furnace. Scope 2 is the electricity it buys from the grid. Scope 3 is everything else: the emissions baked into the products it buys, the waste its customers throw away after using its product, the flights its employees take, the delivery trucks that haul its goods to stores.

Scope 3 is almost always the largest of the three. A clothing brand might produce almost no emissions in its own factories (Scope 1 and 2), but the cotton farms that grow its fabric, the ships that carry it overseas, and the trucks that deliver finished clothes to stores all emit carbon. Those emissions belong to Scope 3. The brand caused them, even though someone else released them into the air.

Companies track Scope 3 because investors, regulators, and customers increasingly want to know the true environmental cost of what they buy. A company that only counts Scope 1 and 2 is hiding most of its footprint. Understanding Scope 3 shows where the real impact lives — and where a company can actually make a difference.

Key Takeaways

  • Scope 3 emissions include everything a company causes indirectly: the materials it buys, the way products are transported, how customers use them, and what happens when they are thrown away.
  • Scope 3 is typically 5 to 10 times larger than Scope 1 and 2 combined, so ignoring it means ignoring most of a company's environmental impact.
  • Companies calculate Scope 3 by estimating emissions from suppliers, logistics partners, and customers based on industry averages when exact data is not available.
  • Reducing Scope 3 often requires working with other companies in the supply chain, not just changing internal operations.

The 15 categories of Scope 3 emissions

The Greenhouse Gas Protocol, the standard most companies use to measure emissions, breaks Scope 3 into 15 categories. Not every company counts all 15 — some do not explore. But the main ones show where the work happens.

Purchased goods and services is usually the largest. If you make a phone, the silicon, glass, plastic, and metals you buy all came with emissions attached. Capital goods covers the machines and buildings you buy to make your products. Fuel and energy-related activities includes the emissions from extracting and transporting the coal or natural gas that power your electricity grid. Upstream transportation and distribution is what it sounds like: trucks, ships, and planes moving your raw materials and finished products before they reach you.

Waste generated in operations counts the emissions from landfills and incinerators that handle your company's trash. Business travel is flights and rental cars your employees use for work. Employee commuting is the drive to the office. Downstream transportation and distribution is the delivery truck that takes your product from the warehouse to the store or customer's home. Use of sold products is often the second-largest category: if you sell a car, the gasoline burned over its lifetime counts as your Scope 3. If you sell a refrigerator, the electricity it draws for 15 years is yours to count.

The remaining categories cover end-of-life treatment (what happens when the product is recycled or thrown away), franchises, investments, and leased assets. Most companies focus on the five or six categories that matter most to their business.

Why Scope 3 is hard to measure

A company knows exactly how much fuel its own trucks burn. It gets a bill for its own electricity. But it does not own the cotton farm or the cargo ship. It cannot install a meter on every supplier's equipment. So companies estimate Scope 3 using emission factors — standard numbers that say "one ton of steel production creates X tons of CO2" or "one kilometer of truck transport creates Y tons of CO2."

A company multiplies the amount of material it buys by the emission factor. If you purchase 100 tons of aluminum, and the industry average is 12 tons of CO2 per ton of aluminum, your Scope 3 from that purchase is 1,200 tons of CO2. The accuracy depends on whether the emission factor matches your actual supplier. A supplier with renewable energy might produce half the average. A supplier in a coal-heavy country might produce double.

Some large companies now ask their suppliers directly for emissions data instead of using averages. This takes more work but gives a truer picture. Smaller companies usually rely on published emission factors from the International Energy Agency, the U.S. Environmental Protection Agency, or industry groups. The numbers are reasonable but not precise.

How companies reduce Scope 3 emissions

Reducing Scope 3 requires working with other organizations, not just changing what happens inside your own walls. A clothing brand cannot cut the emissions from cotton farming by itself — it has to push suppliers to use less water, less fertilizer, and less machinery, or switch to suppliers who already do. A tech company cannot reduce the emissions from shipping unless it works with logistics partners to consolidate shipments or use slower, lower-carbon transport.

The most common moves are: switching to lower-carbon materials (recycled plastic instead of virgin plastic), redesigning products to weigh less (lighter products use less fuel to ship), choosing suppliers with lower emissions, and pushing customers to use products more efficiently or recycle them at the end of life. A car company might design engines that burn less fuel. A software company might encourage customers to use cloud services instead of running their own servers.

Some reductions are fast. Consolidating shipments or changing packaging can happen in months. Others take years: finding a new supplier, building a recycling program, or waiting for an industry to develop lower-carbon alternatives. This is why many companies set Scope 3 reduction targets for 2030 or 2050 rather than next year.

How Scope 3 affects what you buy

When a company publishes its carbon footprint, Scope 3 tells you whether the company is being honest about its impact. A car manufacturer that only counts emissions from its factories is hiding the fact that the cars it sells will burn gasoline for 15 years. A fast-fashion brand that only counts its own operations is ignoring the farms, dyes, and shipping that make up 90 percent of its footprint.

Companies that measure and report Scope 3 are usually more serious about reducing emissions overall. They have looked at their whole supply chain and made a plan. They are also more likely to face pressure from investors and regulators, which means they have skin in the game.

If you are trying to choose between two companies based on environmental impact, look for one that reports all three scopes and explains how it plans to reduce Scope 3. A company that only talks about Scope 1 and 2 is not telling you the full story.

The difference between Scope 3 and carbon offsets

Carbon offsets are a different tool. A company buys an offset when it pays someone else to reduce emissions somewhere else — planting trees, building a wind farm, or funding methane capture at a landfill. Offsets do not reduce the company's own Scope 3 emissions. They are a way to claim the impact is "neutral" without actually changing what the company does.

Most climate scientists and regulators now say offsets should be a last resort, not a substitute for real reductions. A company should first cut its Scope 3 emissions as much as it can — by changing suppliers, redesigning products, and pushing customers toward lower-carbon choices. Only after that should it use offsets for emissions it cannot eliminate. Many companies use offsets to cover Scope 3 emissions they have no realistic way to cut, like the methane released by cows that produce milk for their products.

Frequently Asked Questions

Is Scope 3 the same as my personal carbon footprint?

No. Your personal carbon footprint is mostly Scope 3 from a company's perspective — the emissions from products you buy and use. A company's Scope 3 is the sum of all its customers' use of its products, plus all the upstream emissions from making those products. If you drive a car, your driving emissions are part of the car company's Scope 3.

Why do companies not just measure Scope 3 exactly instead of using estimates?

Exact measurement would require installing sensors on every supplier's equipment and tracking every product through its entire life. That is technically impossible and economically unrealistic. Estimates using industry averages are good enough for companies to identify where the biggest emissions are and where they can make the biggest cuts.

Can a company have negative Scope 3 emissions?

Not in the traditional sense. But a company can claim "carbon negative" if it removes more carbon from the atmosphere than it emits across all three scopes — usually by funding large-scale tree planting or carbon capture projects. This is rare and often controversial because the removal projects may not be permanent or may not happen as promised.

Do all companies report Scope 3?

No. Scope 3 reporting is not required by law in most countries, though that is changing. The European Union now requires large companies to report it. In the United States, the Securities and Exchange Commission has proposed rules that would require public companies to disclose Scope 1 and 2, with Scope 3 coming later. Many companies report Scope 3 voluntarily to attract investors and customers who care about climate impact.

If a company reduces Scope 3, does that mean the product is actually lower-carbon?

Usually yes, but not always. A company might reduce its reported Scope 3 by switching to a supplier with lower average emissions, even if that supplier is not actually more efficient — just located in a country with cleaner electricity. The real test is whether the company is making products that use less energy or materials, or designing them to last longer or be recycled.