The UK CBAM starts on 1 January 2027, and the first return, for the whole of 2027, is due by 31 May 2028. That sounds a long way off, but the figure you need from your supplier only exists if they monitor their emissions through 2027 and have them verified. If you want to use real data rather than the government's defaults, the time to ask is now. This post sets out what to ask for and gives you an email you can copy.
If you are not sure you are in scope, try the free UK CBAM registration checker first, or read the complete guide to the UK CBAM.
Why it is worth asking
Your CBAM charge is the weight you import times an emissions intensity, times the rate for the quarter. The intensity is either your producer's verified figure or the government's default for the commodity code. The defaults have a 10% markup in every sector except fertiliser, because the government wants there to be no advantage in not finding out the real figure. And once you file a return using defaults, you can't amend it later with actual data. Our post on the illustrative 2027 rates and default values shows what the markup costs, and how to work out a UK CBAM bill walks through the sum.
What to ask for
| What | Why you need it |
|---|---|
| Verified emissions intensity per commodity code | Tonnes of CO2e per tonne of product, for each 8-digit commodity code you buy. This is the number that goes on your CBAM return in place of the default value. |
| The monitoring year | For goods imported in 2027, HMRC says to ask for the verified figure for calendar year 2027, or for 2026 if 2027 isn't available. From 2028 you can use the most recent verified figure from either of the two calendar years before import. |
| The verification report or a verification summary | The producer gives you either the full report or a summary for the good you bought. You must keep it for six years as evidence. |
| Installation details | The name, address and country of the factory or plant that made the goods. Figures are for one installation, not a whole company. |
| The verifier | The verifier must be accredited and independent of the installation. Ask who it is and who accredited them, so you can check. |
| Carbon price paid | If the goods were subject to a carbon price where they were made, a completed carbon pricing verification form lets you claim Carbon Price Relief. |
Two points trip people up. First, the figure is for one installation, so a supplier with several plants may have several figures. Second, it covers a calendar year and has to be verified after the year ends, so 2027 figures won't be ready until 2028. HMRC's guidance gives the example of a good imported on 25 June 2027: you ask for the intensity covering 1 January to 31 December 2027 and use it on the return due from 31 May 2028.
The email template
Copy this, fill in the parts in square brackets, and send it to your contact at each producer. If you buy through a trader or agent rather than direct from the mill or plant, send it to them and ask them to pass it on.
Subject: Emissions data for UK CBAM: [your product and order reference] Dear [name], From 1 January 2027 the UK charges a Carbon Border Adjustment Mechanism (CBAM) tax on imports of [steel / aluminium / cement / fertiliser / hydrogen]. As the importer, we pay it on the emissions in the goods we buy from you. If we can't get verified data from you, we have to use the UK government's default values, which are set high on purpose. Your own figure is likely to make your goods cheaper for us to import, and it helps us keep buying from you. Please could you send us the following for each installation that makes goods for us. 1. Emissions intensity. Your verified emissions intensity, in tonnes of CO2e per tonne of product, for each of these 8-digit commodity codes: - [commodity code]: [product description] - [commodity code]: [product description] We need figures for calendar year 2027 (1 January to 31 December 2027). If your 2027 figures will not be verified in time, please send your verified figures for calendar year 2026 as well. 2. Verification. The verification report for each year, or a verification summary for each good we buy. Please tell us when you expect the 2027 report to be ready; our first UK CBAM return is due by 31 May 2028. 3. Installation details. The name, full address and country of the installation (factory or plant), and any identifier it has in other CBAM registries. 4. Your verifier. The name of the verification body, the accreditation body that accredited it, and confirmation that it is independent of your installation. If your figures were verified for the EU CBAM, please tell us, and confirm whether the verification also meets the UK CBAM requirements. 5. Carbon price paid. If your installation pays a carbon price (for example under an emissions trading scheme or carbon tax), the name of the scheme and a completed carbon pricing verification form, so that we can claim UK Carbon Price Relief. 6. Your contact. Who we should speak to about these figures, and how best to reach them. If you are not monitoring emissions this way yet, please let us know by [date] whether you plan to monitor calendar year 2027, so we can plan our return. HMRC's guidance for overseas producers is at https://www.gov.uk/guidance/monitoring-emissions-asan-overseas-installation-producing-carbon-border-adjustment-mechanism-cbam-goods-exported-to-the-uk Thank you for your help. Kind regards, [your name] [job title, company, phone]
Tips for getting an answer
- Send it in their language as well as English if your contact works mainly in another language. The commodity codes and numbers are the same everywhere.
- Give the codes. Looking up your own 8-digit commodity codes from your import declarations saves the supplier guessing which products you mean.
- Mention the EU. Producers selling into the EU have been asked for similar figures since the EU CBAM began. They may already monitor emissions; ask them to confirm the figures and verification also meet the UK rules. Our post on how the EU and UK CBAM differ explains why the two are not identical.
- Ask early and diarise a chaser. Ask in 2026 whether they will monitor 2027, and chase in early 2028 for the verified report.
- Keep everything. HMRC expects you to keep the verification report or summary, and any carbon pricing verification form, for six years.
The same per-tonne figure also improves your own carbon footprint, because it can replace a spend-based estimate for those purchases. Our post on CBAM data and your Scope 3 works through an example. For data requests beyond CBAM, see what customers can and can't ask of suppliers.
How Carbon Recycling helps
Carbon Recycling is not a CBAM verifier, customs agent or tax adviser, and it doesn't file CBAM returns. It helps you collect supplier figures and use them in your carbon reporting.
On the Growth plan, supplier data requests send each supplier a secure link, with no account needed on their side. You can paste the template above into the request message. The supplier sends back the emissions for what they supplied to you over the period and how they calculated it, and once you accept it the figure goes into your Scope 3. The CBAM pack, coming soon, works out the embedded emissions and the UK CBAM charge on your imports.
The 14-day free trial lets you add data and see how your reports look. Printing, saving and downloading need a paid plan.