CBAM Reporting Explained: What UK Importers and Exporters Need to Know

What Is CBAM?

The Carbon Border Adjustment Mechanism (CBAM) is a carbon pricing tool that puts a cost on the emissions embedded in certain imported goods, so products made outside a strict carbon-pricing regime face a similar carbon cost to goods made inside one. The EU introduced CBAM in October 2023, and the UK is introducing its own version from January 2027.

Which Goods Are Affected?

CBAM currently covers a defined list of carbon-intensive goods: iron and steel, aluminium, cement, fertilisers, hydrogen and electricity. If your business imports, exports, or moves any of these goods between the UK and the EU, CBAM reporting obligations are likely to apply somewhere in your supply chain.

What Does Reporting Involve?

During the transitional phase, importers report the embedded emissions of covered goods each quarter, without having to pay a charge. Once the full mechanism takes effect, businesses need to purchase certificates reflecting the carbon price already paid, if any, in the country of origin. Getting the underlying data right, from supplier emissions declarations to the correct commodity code on each shipment, is the difference between a straightforward return and a compliance headache.

Common Reporting Mistakes

Using the wrong commodity code is the most common one. CBAM obligations are triggered by the code on the customs declaration, so misclassified goods mean reporting gets missed or duplicated, exposing the business at review. Missing supplier emissions data is another: where actual figures are not available from the producing installation, default values apply, and they are usually less favourable than the real number. Late or incomplete quarterly returns are the third. The reporting deadlines are unforgiving, and missing a filing window can trigger penalties even during the transitional period.

How GEIM Helps With CBAM Reporting

We handle the customs declaration and CBAM reporting together, so the commodity codes, origin data and emissions figures used across both stay consistent from the outset. Our CBAM Reporting page covers the service in full, or get in touch if you are unsure whether CBAM applies to your goods.