CBAM reporting-only transition begins

Core record and legal stage

On 1 October 2023 the CBAM transitional stage started pursuant to the 2023 founding regulation and the Commission's implementing rules. This was a scheduled commencement of existing law rather than a fresh parliamentary enactment. From that date covered importers began collecting data for quarterly emissions reports. No CBAM certificate purchases were required for imported goods during the reporting-only period, which ran through the end of 2025. Confusing this reporting stage with the subsequent definitive carbon charge overstates importers' cash obligations in 2023.

Mechanism

Companies had to identify covered goods by customs classification, quantify imports and seek embedded-emissions data from overseas facilities. The first report was due by the end of January 2024. Producers already monitoring energy use and process emissions had an advantage in responding to importers' requests. For smaller supply chains, discovering the appropriate factory, process and emissions boundary could be more difficult than submitting the eventual form. The obligations were data-intensive despite the absence of a contemporaneous certificate price.

Decision-makers, money and stakes

The administration could gather information about actual import volumes and production intensities before the system became financially definitive. An EU buyer could use those reports to estimate whether a supplier using cleaner technology might become more competitive after 2026. A British or Canadian manufacturer could plan emissions monitoring to preserve market access. Compliance services may gain customers, but the cost to individual companies cannot be inferred from the number of reporting quarters. Documentation quality is as important as volume.

Strongest counter-view

The main counter-view is that repeated quarterly reporting imposes an excessive fixed burden on importers trading modest quantities. That concern became relevant to the later 50-tonne simplification. Equally, a reporting-only phase may be defended as proportionate preparation for a more complex final regime. Analysts should compare initial report completeness, default-value reliance, subsequent correction rates and later changes to importer eligibility before concluding the transition was efficient.

What to watch

Starting a compliance calendar is an economically meaningful act even without a transfer of funds to a government. It influences information systems, hiring and sourcing decisions. However, the date cannot prove that foreign factories reduced emissions in response. Such attribution would require installation-level measures before and after the reporting requirement and consideration of energy prices, technology upgrades and other environmental regulations outside the EU.

Early compliance economics

For a small EU manufacturer importing a few batches of metal inputs, quarterly reporting can impose a sizeable fixed expense even if no CBAM certificates are due. For a large importer, building a reusable reporting pipeline may spread the expense over many transactions. This explains why the reporting start generated concerns about proportionality before direct carbon adjustment payments began. The relevant performance indicators include hours of compliance work, corrected reports, supplier data coverage and whether methods improved over successive quarters. These should be compared separately from import volumes.

The first reporting cycle as a natural test

The first quarterly deadline, at the end of January 2024, forced importers to turn a legal requirement into operational data collection. Procurement teams had to establish which imported consignments were covered, identify origin installations and align customs quantities with emissions information from suppliers. Those practical steps matter because customs codes, production routes and emissions calculation periods are different data fields. A missing installation record cannot be repaired merely by knowing the declared value of a shipment. A buyer might respond by changing its supplier questionnaire or contract terms; such a response is economically plausible, but the fact of the 1 October start alone does not prove it occurred across the market.

A more precise test of proportionality

The administrative burden is particularly visible when a company has many small shipments from different factories. Even without certificates to purchase, its reporting duty can require multiple information requests and reconciliation work each quarter. Larger firms can spread software and verification-related preparation costs across more tonnes, whereas occasional importers may face a high cost per tonne of data gathered. That distributional issue later fed into the political case for changing the small-importer threshold. The right evidence is not only how many businesses submitted reports, but how many tonnes and associated embedded emissions they covered. Comparing 2023 paperwork costs with 2026 certificate liabilities without separating these components would misstate the phased policy.