How is a UK CBAM figure expressed for cement and fertiliser?
For most UK CBAM goods, the figure is tCO2e per tonne of the good. Cement is measured per tonne of clinker and fertilisers per tonne of nitrogen contained, then converted to tCO2e per tonne of the mixture actually imported, using equations in HMRC's emissions and verification force of law notice.
Why these two goods are different
Cement and fertilisers are imported in many mixtures, concentrations and compositions. A tonne of slag cement holds less clinker than a tonne of OPC; a tonne of NPK holds less nitrogen than a tonne of urea. So the plant's verified figure is set per tonne of clinker or nitrogen, and only then turned into a figure per tonne of the product shipped.
Defaults skip the conversion
HMRC publishes its cement and fertiliser defaults per tonne of product: grey Portland cement (2523 29 00) is 1.375 tCO2e per tonne and ammonium nitrate (3102 30 90) 2.600. An importer using a default multiplies it by the tonnes imported. The clinker or nitrogen step only applies to actual verified data.
What the importer reports
- The weight imported, in kilograms; HMRC converts it to tonnes.
- The emissions intensity per tonne of the good imported, already converted.
- A verified figure that relates to one calendar year of production.
What to keep ready at the plant
- Clinker share of each cement grade, batch by batch, from your quality records.
- Nitrogen content of each fertiliser grade, from the certificate of analysis.
- Production tonnes per grade for the calendar year, so the verifier can tie the totals.
The idea in numbers (simplified)
- Example verified figure: 0.85 tCO2e per tonne of clinker.
- A cement with 70% clinker: 0.85 x 0.70 = 0.595 tCO2e per tonne of cement.
- Example fertiliser figure: 3.0 tCO2e per tonne of nitrogen; urea at 46% nitrogen: 3.0 x 0.46 = 1.380 tCO2e per tonne of urea.
A simplified picture of the conversion. The force of law notice's equations decide the real figure.
What Senseible does here
Senseible reads clinker, gypsum, slag, fuel and gas invoices with production by grade, so the clinker or nitrogen basis is on record before the verifier asks. We build the figure from your records and check every figure in-house; for the UK it must then be verified by a verifier accredited for UK CBAM. Have your own verifier? Send it to them.
Sources: HM Treasury and HMRC, UK CBAM policy summary, HMRC, UK CBAM cement default values (published 16 October 2026), HMRC, UK CBAM fertilisers default values (published 16 October 2026)
Last reviewed 2026-11-03.