Do I have to answer a customer's carbon questionnaire?

There is no law requiring an SME to, but it is often a condition of keeping or winning the contract. If you can't answer every question, answer what you can, say what you're doing about the rest, and give a date.

What if I've never measured my emissions?

Say so honestly, and say when you will have figures. A year of energy, fuel and travel data is enough for a first Scope 1 and 2 footprint, which most businesses can produce within a few weeks.

Can I just send my total emissions?

Send totals by scope, the reporting period, the method and the factor set. A single number with no period or method is hard for the customer to use and may be marked down.

How do I work out the emissions for one customer?

The simplest accepted way is to allocate your total by that customer's share of your revenue. If your products differ a lot in carbon intensity, allocate by a physical measure such as units, weight or hours instead, and explain the method.

Should I share my figures publicly?

If you bid for public sector contracts over £5 million a year, your Carbon Reduction Plan must be published on your website. Otherwise it's your choice, though a published plan saves answering the same questions repeatedly.

Is it a problem if my emissions went up?

Not if you explain why. Growth, a new site or better data can all increase emissions. Buyers look for honest figures, a credible plan and intensity ratios that show whether you are becoming more efficient.

A customer has asked for your carbon emissions: what to send

When a customer asks for your carbon emissions, send your Scope 1 and Scope 2 figures in tonnes of CO2e for your latest 12-month period, any Scope 3 you have measured, the method and UK government factor year you used, and your reduction targets or Carbon Reduction Plan. If you haven't measured yet, say so and give a date when you will.

Updated 3 October 2026 by the Carbon Recycling team. Figures use the official UK government conversion factors and are checked against the current gov.uk guidance.

Why customers are asking

Your emissions are part of your customer's Scope 3. A business that reports its own value chain emissions, or has set a science-based target, needs figures from its suppliers to measure and cut them. Public sector buyers ask for a Carbon Reduction Plan under PPN 006, and the NHS asks its suppliers for a net zero commitment or Carbon Reduction Plan depending on contract size. Listed companies reporting under the new UK Sustainability Reporting Standards from 2027 will need more of this data too. So the questions arrive in tenders, in supplier onboarding forms, in platforms such as CDP's supply chain programme and EcoVadis, and in plain emails.

What they usually ask for

Question	What a good answer includes
Do you measure your greenhouse gas emissions?	Yes or no, the standard (GHG Protocol), the period, and whether Scope 3 is included
What are your Scope 1 and 2 emissions?	Tonnes CO2e for each scope, location-based Scope 2, and market-based too if you're on a renewable tariff
What are your Scope 3 emissions?	The categories you measured and their totals, and which you haven't measured yet
Do you have a reduction target?	Baseline year, target year, percentage and which scopes it covers
Do you have a net zero commitment or Carbon Reduction Plan?	A link to the published document and the date it was approved
Are your targets science-based?	Only say yes if the SBTi has validated them; otherwise describe the target as it is
What are the emissions associated with our account?	An allocated figure, with the allocation method (see below)

Step by step: answering a request

Check the deadline and format. Some requests are a single question in a tender; others are a portal with dozens of fields. Note which questions are scored or mandatory.
Use figures you already have. If you've done an SECR report or Carbon Reduction Plan, the Scope 1, 2 and some Scope 3 figures are already calculated. Use the same period and numbers, so you never give two customers different answers.
Fill the gaps quickly. If you haven't measured, a Scope 1 and 2 footprint needs only your gas and electricity bills and vehicle fuel for a year. Our kWh to CO2e calculator gives a first figure in minutes, and our footprint guide covers the rest.
State the basis. Reporting period, boundary (usually operational control), the GHG Protocol, and the UK government conversion factor year.
Be precise about what's missing. "Scope 3 categories 1 and 2 not yet measured; we will report them for the year to March 2027" scores better than silence or a guess.
Attach or link your plan. A published Carbon Reduction Plan answers most of the target and commitment questions in one go. Our free template follows the government format.
Keep a copy of every answer. Customers compare years. Next year you'll want to show progress against what you told them.

Working out emissions for one customer

Some customers want "their share" of your emissions, so they can put it in their Scope 3 category 1. The GHG Protocol's Scope 3 Standard accepts allocation. The usual approach for an SME is economic allocation:

Customer's share = your total emissions × (revenue from that customer ÷ your total revenue)

For example, if your Scope 1 and 2 total is 60 tCO2e and a customer is 15% of your revenue, their share of your Scope 1 and 2 is 9 tCO2e. Say which scopes you included; most customers want at least Scopes 1 and 2, and ideally your upstream Scope 3 as well. If your products or services differ a lot in carbon intensity, a physical basis such as units shipped, tonnes, vehicle miles or staff hours on the contract is more accurate. Whichever you use, state it and keep it the same each year.

Mistakes that cost points or cause trouble

Claiming "carbon neutral" or "net zero" because you buy offsets. Buyers and regulators treat these claims sceptically. Read our offsetting guide before using either phrase.
Saying your targets are "science-based" when they have not been validated by the SBTi. See our guide to science-based targets for SMEs.
Reporting only market-based Scope 2 on a green tariff, so electricity shows as zero with no explanation.
Using out-of-date or mixed factors. State the year of the UK government factors you used.
Giving different numbers to different customers for the same period.

Asking your own suppliers

The same logic runs up your supply chain. Once you report Scope 3 category 1, your best data comes from your largest suppliers. Ask them the same short set of questions: Scope 1 and 2 totals, the period, the method, and their revenue so you can allocate. Start with the few suppliers that make up most of your spend; you don't need everyone.

How Carbon Recycling helps

Your footprint, Carbon Reduction Plan and SECR figures come from one set of data, so every answer you give is consistent. Each figure shows the government factor behind it, which is what customers' sustainability teams check. On the Growth plan you can also send data requests to your own suppliers and record their answers against the right Scope 3 category.