Scope 3: your biggest regulatory headache is also your biggest opportunity

Most mid-sized businesses get to know the details of Scope 3 for the first time in the form of a request. A large customer sends a supplier questionnaire, a lender asks about transition risk, or a parent group needs data for its own report. The natural response is to treat it as compliance: find the minimum acceptable answer, hand it to whoever has "sustainability" in their job title and move on.

While that is understandable, it is also a missed opportunity, because the data you need to answer the request is the same data you need to find cost.

The scale of what sits outside your walls

CDP and BCG reported in 2024 that companies disclosing through CDP had supply chain emissions on average 26 times larger than their own operational emissions. The same work found companies were twice as likely to measure Scopes 1 and 2 as Scope 3, and only 15% had set a Scope 3 target. Only 41% engaged suppliers on climate at all.

Put plainly, most businesses have measured the small part of their footprint and left the large part as an estimate. For a manufacturer, distributor or retailer, the large part is dominated by a short list: purchased goods and materials, inbound and outbound transport, packaging, and what happens to products at the end of their life.

Look at that list again from a P&L point of view. Materials are usually the biggest cost line. Freight is among the fastest rising: Logistics UK reported diesel up 36% and vehicle operating costs up more than 12% in the year to April 2026. Packaging now carries an explicit charge under UK extended producer responsibility, and from the second year of the scheme that charge varies with recyclability. The categories that dominate your emissions are, almost always, the categories where cost reduction lives.

Carbon is starting to carry a price

For some materials the link between carbon and cost is no longer indirect. The EU's Carbon Border Adjustment Mechanism moved into its definitive period on 1 January 2026, so importers of goods such as steel, aluminium, cement and fertilisers above a 50-tonne annual threshold must buy certificates covering embedded emissions, with sales of certificates starting in February 2027. The UK plans its own CBAM from January 2027. Suppliers with lower-carbon production will increasingly be able to show it in price.

Packaging is similar. Under the illustrative year-two EPR fees published in December 2025, red-rated packaging was expected to attract fees around 20% above the base amber rate, with green-rated packaging receiving a discount of around 9%. Design choices that cut emissions and improve recyclability now show up on an invoice.

What the Omnibus changes mean for suppliers

The EU's Omnibus simplification cut the number of companies that must report under CSRD and introduced a value chain cap. Companies with up to 1,000 employees are treated as protected undertakings and can decline data requests that go beyond a voluntary standard. For many mid-sized suppliers, that removes the fear of unlimited questionnaires.

It does not remove the commercial question. Large customers still have targets and still choose between suppliers. A supplier that can give a credible footprint for its products, and a plan to reduce it, is easier to buy from. The cap sets the floor for what can be demanded, not the ceiling for what wins business.

How to approach it

Start with a spend-based baseline. Multiply purchase ledger spend by category by published emission factors. It is rough, it takes weeks rather than months, and it is enough to rank your hotspots.

Then replace estimates with activity data only for the top few categories: tonnes of material by type, freight by mode and lane, packaging by material and weight. That is where both the emissions and the money are, and where precision changes decisions.

Give ownership to procurement and operations, with the sustainability lead as coordinator. The levers are supplier choice, specification, mode, load fill and design. A sustainability team cannot pull those on its own.

Be honest about your trade-offs. Some reductions pay back quickly: better load fill, lighter packaging, fewer expedited shipments. Some cost more, such as recycled content at a premium or a lower-carbon supplier with a higher price. Model both and decide case by case rather than assuming every carbon reduction is free.

A business that does this has a better answer for its customers and a clearer list of savings. The questionnaire becomes the cheapest part of the exercise.

Our Supply Chain Carbon Snapshot, launching soon, is designed to give a first spend-based view of where your hotspots sit.