The US Scope 3 Blind Spot: What Unreliable Supplier Emissions Data Is Costing You

Key takeaways

• You’re likely underestimating your Scope 3 emissions. US suppliers in the EcoVadis network with verified emissions data report Scope 3 footprints roughly 2x larger than peers reporting low-reliability figures – closing this visibility gap could be worth about $5 per ton of carbon in cost savings by 2030.
• Only about a quarter of US suppliers have data reliable enough for Scope 3 accounting. 47% of US suppliers in the network report Scope 1&2 data, but only half of that is high-reliability or verified.
• A small group of suppliers drives most of the carbon impact. The top 10% of US emitters account for 96% of emissions reported by US suppliers. They’re also highly connected, so improving their data reliability improves visibility for dozens of buyers at once.
• Engaging suppliers works. US suppliers that engage their own suppliers on carbon are 6x more likely to hit science-based reduction targets. Start with your high-impact suppliers first to accelerate your Scope 3 efforts.

US procurement and sustainability teams don’t lack reasons to act on supply chain emissions. 94% of North American companies reported higher costs from climate impacts in the last year, California’s SB 253 is turning Scope 3 disclosure into a legal requirement, and the EU’s CBAM is turning unverified carbon data into a cost. But what many lack is the reliable supplier emissions data needed to accurately identify hotspots and take action. 

The 2026 Carbon Action Report, EcoVadis and Kearney’s analysis of the carbon performance of roughly 56,000 suppliers, makes that case directly. Of those, 5,400 are US-based, and the findings below draw on a US-specific cut of that data.

“Companies are making capital and sourcing decisions on carbon numbers they can’t actually trust.”

Pierre-François Thaler
Co-Founder and Co-CEO, EcoVadis

Your Scope 3 footprint is bigger – and more costly – than your data says

US suppliers with high-reliability or verified data report a median Scope 3 footprint 6.6 times larger than their own operational emissions. This drops to 3.5 times larger for those working with low-reliability data. This nearly 2x gap represents potential hidden emissions that could be shaping your sourcing, target setting, and capital decisions without your knowledge. 

That gap has a price. Suppliers with high-reliability or verified data are cutting operational emissions faster – around 4.5% a year versus 3.0% for low- and medium-reliability peers. That accelerated rate of reduction is worth roughly $5 per ton of carbon in cost savings annually across a typical supply chain by 2030.

Collecting more accurate supplier data can make your reported footprint grow before it shrinks. Where primary supplier figures are missing, upstream footprints get estimated from spend using industry averages that consistently understate emissions; replacing those estimates with real data gives you a more accurate baseline from which reductions can be measured, defended, or tied to return on investment.

“While better data may initially expand a company’s footprint, it provides the critical foundation for making better decisions, driving measurable reductions, and demonstrating ROI on investment.”

Dexter Galvin
SVP & Climate Ambassador, EcoVadis

Only about a quarter of your US suppliers may have reliable carbon data

Of the 5,400 US suppliers assessed by EcoVadis, 47% report Scope 1&2 data. Around half of that data meets high-reliability or third-party verified standards, which suggests only about a quarter of your US suppliers may be providing emissions figures solid enough to use for Scope 3 accounting. 

37% of US suppliers report Scope 3 data to the EcoVadis network, but only about 1 in 5 of them are using primary data for their Scope 3 calculations. Only 8% of US suppliers reporting Scope 3 have achieved third-party verification.

This gap could leave you exposed to real compliance risk. Starting in 2027, more than 2,600 US companies with over $1 billion in revenue that do business in California must disclose Scope 3 emissions under SB 253, regardless of federal policy. The EU’s Carbon Border Adjustment Mechanism raises the stakes further: US producers of covered goods such as iron, steel, and aluminum now have European customers who must report the embedded carbon in their imports, and starting February 2027, those customers will pay for that carbon through certificates – at default rates unless the supplier can provide verified figures.

US emissions are concentrated in a highly connected group of suppliers

The top 10% of US emitters account for 96% of the emissions reported by US suppliers in the EcoVadis network. That small group is also extraordinarily well connected: each of these suppliers connects to 127 buyers on average, compared to 72 for the global top decile. Even typical US suppliers average 66 buyer connections versus 35 globally.

Concentration plus connectivity changes the economics of supplier engagement. You don’t need to improve data reliability across your entire supply base to gain a clearer picture of your Scope 3 footprint, or to capture the cost savings that come with it. Helping one high-emitting US supplier reach verified data can improve Scope 3 visibility for you and dozens of other buyers at once – and because carbon maturity cascades, engaging your Tier 1 suppliers on data quality is often what gets their own Tier 2 suppliers reporting reliably too.

Your suppliers are more likely to hit their targets when they engage theirs

US suppliers that actively engage their own suppliers on carbon are 6x more likely to be on track against science-based targets than those that don’t (31% versus 5%). Data reliability drives whether that engagement happens at all: 62% of US suppliers with verified Scope 1&2 data go on to engage their own suppliers, against 9% of low-reliability peers. 

Fewer US suppliers set carbon targets than the global average, at 27% versus 33%. But of those that do, 54% are on track to deliver, against 45% globally. US suppliers may commit less often, but they’re following through more consistently on the targets they do set.

Where to start

Three steps separate the programs that move from the ones that stall.

1. Find your hotspots: Identify the highest-emitting suppliers in your US supply base, then check how many other buyers they serve. The most connected are the ones where improvement travels furthest.
2. Move those suppliers up the reliability curve: Getting a supplier from estimated to verified Scope 1&2 data does more for your Scope 3 accuracy than adding coverage at the long tail – and it’s where the $5-per-ton opportunity is.
3. Engage rather than request: Formal requirements set the floor, but support, training, and commercial incentives are what actually shift supplier behavior.

“The fastest results come from focusing on your highest-emitting suppliers first, backed by contractual requirements and real incentives, rather than trying to fix your entire supply chain at once.”

Angela Hultberg
Global Head of Sustainability, Kearney

The EcoVadis Carbon Action Manager is built for this work. The platform assigns a data reliability level to every emissions figure suppliers submit, so you can see which numbers are usable for primary accounting before you build targets or strategies around them. It also segments suppliers by carbon maturity, which is what lets you direct engagement to where it matters most. 

Your Scope 3 breakthrough is within reach, and engaging your hotspot suppliers can get you there faster. Read the full 2026 Carbon Action Report for more insights, including a Scope 3 playbook built from interviews with leading global buyers.