UK ports challenge EU carbon leakage claims

The British Ports Association has challenged the argument that higher UK container traffic in 2025 chiefly reflects shipping lines trying to avoid European Union maritime emissions charges. In commentary reported on 15 October 2026, the association points instead to capacity investment at London Gateway and a restructuring of container shipping alliances. This is a disagreement about why traffic patterns changed, not a finding that emissions pricing cannot affect any route.

The disagreement follows work by Spain’s state-owned Puertos del Estado, whose EU ETS Observatory tracks changes in long-distance shipping connectivity between EU ports and nearby non-EU gateways. Researchers have highlighted UK ports as possible beneficiaries of redirected services and discussed measures against so-called carbon leakage. Treating that monitoring as grounds for designating Felixstowe, London or Southampton as neighbouring container transhipment ports would require a separate EU regulatory decision; the reported discussion does not amount to an enacted designation.

According to the BPA analysis reproduced in trade reporting, UK container handling increased by approximately 600,000 physical units in 2025, with around 500,000 of the increase attributed to the London port area. The association argues that the concentration of growth is more consistent with expanded London Gateway capacity than with a general regulatory advantage for UK ports. These are figures and an interpretation advanced by the BPA; they should not be recast as independently reconciled twenty-foot equivalent units (TEU), since a count of containers and a TEU measure are different.

Shipping alliance changes provide another identifiable explanation for traffic shifting between terminals. The Gemini Cooperation’s network placed Maersk’s principal Asia–Europe UK calls at London Gateway rather than Felixstowe, affecting the distribution of scheduled calls and associated container lifts. A larger share for one gateway does not necessarily mean the national market increased by the same amount. Terminal capacity, available berth windows, vessel-network design and inland access can all alter a carrier’s port choice independently of the emissions regime.

The two sides also draw different conclusions from TEU-miles. The Spanish observatory defines this measure as the nominal TEU capacity of vessels arriving at a port multiplied by the distance travelled; it is not a count of loaded containers discharged or imported cargo received. Changing the sequence of calls can alter the distance attached to a particular port even where a vessel continues visiting multiple gateways. The measure is useful for observing long-distance service connectivity, but it cannot alone establish how many containers have been diverted from an EU port to a UK terminal.

Puertos del Estado’s July 2026 update, which draws on vessel monitoring and adds container tracking, reported a five-percentage-point decline in direct connectivity for northern European ports and an 18-point decline for the eastern Mediterranean in its chosen measures. The Spanish organisation regards such changes as warning signs for the competitiveness of EU maritime gateways. The BPA disputes the attribution of UK growth specifically to carbon avoidance. Both positions require care: observed changes are real within the stated metrics, while the causal contribution of emissions costs remains contested.

EU ETS coverage provides a reason that carriers might consider a different port rotation. The scheme generally captures all emissions on voyages between EU ports and half of emissions on journeys between an EU and non-EU port, alongside emissions produced within EU ports; allowance surrender was phased in after 2024. A non-EU call can therefore change the calculation, but it may also add steaming time, handling costs, an inland detour or missed connections. Establishing the actual incentive on a particular rotation requires those commercial costs to be compared with the applicable emissions charge.

UK Department for Transport data for January to March 2026 provide an independent illustration of traffic redistribution, although they concern a later period than the 2025 BPA totals. London’s container traffic rose by 65,000 units, or 19%, against the same quarter of 2025, while Felixstowe fell by 88,000 units, or 16%. The department attributed the opposing movements partly to a major carrier relocating operations from Felixstowe to London Gateway. Those official figures support the role of network restructuring but do not quantify any effect from the EU ETS on 2025 traffic.

Domestic maritime emissions entered the UK ETS in July 2026, whereas the UK authority’s November 2025 consultation proposed extending the scheme to 50% of international voyage emissions from 2028. That proposed international extension has not been verified as enacted in the material reviewed for this article. EU discussions about neighbouring transhipment-port rules are likewise distinct from an already operative decision affecting the named British gateways. Treating either prospective policy as settled would obscure the regulatory position that carriers face today.

Two forms of evidence are needed to assess the claim more decisively: physical container movements between ports and voyage-level information on network economics, including emissions liability, berth capacity and onward freight costs. The BPA’s explanation and the Spanish observatory’s connectivity analysis can both describe elements of the same restructuring without proving the same cause. For now, the verified development is a public dispute over the interpretation of 2025 traffic changes, with the proposed anti-avoidance treatment still a policy question rather than enacted law.