# We capture or sell carbon dioxide from our process. Can we subtract it for UK CBAM?

Canonical: https://senseible.earth/answers/uk-cbam-co2-sold-or-sent-to-another-plant

Only for uses on HMRC's list: capture, long-term geological storage, or chemically bound products such as precipitated calcium carbonate, backed by proof along the whole chain. In all other cases, carbon dioxide (CO2) sent out of the plant must be counted in the emissions report for the UK Carbon Border Adjustment Mechanism (CBAM).

## What counts as not emitted

- CO2 used within the installation, or transferred out, for capture that is monitored under the rules.
- CO2 sent to an installation, non-CBAM entity or transport network for long-term geological storage that is monitored under the rules.
- CO2 transferred out and used to make precipitated calcium carbonate, where it is chemically bound.

## The proof HMRC wants for a transfer

For CO2 sent to another installation or a non-CBAM entity, evidence must cover the whole chain of custody: the storage location, the receiving installation or entity, the transport operators or method, and the fraction stored or used in chemically stable products compared with the total sent out.

## Where the guide's wording needs a question to your verifier

- Section D4.6.5 lists storage and chemical binding as separate bullets. Section D4.6.5.2 says pure or almost pure CO2 can be subtracted "on the provision that both of the following conditions are met": the purpose is storage or transport for long-term geological storage, and the CO2 is used to produce products where it is permanently chemically bound.
- The guide gives urea feedstock as an example of pure CO2 being transferred, but the list of not-emitted uses does not name urea. Ask your verifier how a urea transfer is treated before you subtract anything.
- Inherent CO2 inside a transferred gas counts as your emission if it is emitted downstream, for example vented or flared.

## How to measure it

- For CO2 transferred between installations, the guide says a measurement-based method must be used; it recommends a continuous emissions monitoring system (CEMS) on the CO2 stream. Share the results with the other party.
- For CO2 permanently chemically bound into products, a calculation-based method is preferred, with the reactions and stoichiometric factors written in the monitoring plan.
- Name the receiving and sending installations in the monitoring plan.

## Example: 100,000 tonnes of direct emissions

- Plant emissions before any transfer: 100,000 tCO2
- 10,000 tCO2 sent for long-term geological storage with chain-of-custody proof: 100,000 minus 10,000 = 90,000 tCO2 reported
- 10,000 tCO2 sold for a use not on the list: stays in the 100,000 tCO2

The tonnages are examples. tCO2 means tonnes of carbon dioxide. The storage line assumes your verifier accepts storage alone, which the guide's wording leaves open (see above). Whether a given use qualifies is for your verifier to judge against the guide.

## What Senseible does here

Senseible reads fuel invoices and electricity bills into monthly records. The standard product does not measure CO2 streams or confirm where captured CO2 ends up. A verifier accredited for UK CBAM must still verify the figure.

- [What a UK CBAM monitoring plan holds](https://senseible.earth/answers/uk-cbam-monitoring-plan-contents)
- [UK CBAM system boundaries](https://senseible.earth/answers/uk-cbam-system-boundaries)
- [Who can verify an Indian plant](https://senseible.earth/answers/uk-cbam-who-can-verify-indian-plant)
- [UK CBAM for Indian exporters](https://senseible.earth/uk-cbam)

Sources: [HMRC, Carbon Border Adjustment Mechanism (CBAM): technical guide for monitoring, reporting and verification](https://assets.publishing.service.gov.uk/media/6ad219fe0f7b53973e02680f/CBAM_technical_guidance.pdf)

Last reviewed 2026-11-06. Read from technical guide sections D4.6.5 to D4.6.5.4 on 6 November 2026. The guide is open for feedback until 13 November 2026 and HMRC may change it before 1 January 2027.