The European Union’s Carbon Border Adjustment Mechanism (CBAM) entered its transitional phase in October 2023. The United Kingdom confirmed its own CBAM in December 2023, with implementation expected by 2027. Japan has taken a different route, launching the GX League in 2023, a voluntary emissions trading system with a planned transition to mandatory carbon pricing by 2026. For mid-market exporters — companies with annual revenues between £10 million and £500 million — these three regimes represent a new layer of regulatory complexity that directly affects cost structures, supply chain configuration, and market access.
This article examines the key differences between the three mechanisms, assesses how mid-market exporters are responding, and identifies the commercial implications for businesses that trade across these jurisdictions.
The Three Regimes: Scope, Timing, and Price Signals
The EU CBAM currently covers imports of cement, iron and steel, aluminium, fertilisers, electricity, and hydrogen. Importers must purchase CBAM certificates at a price linked to the EU Emissions Trading System (EU ETS) allowance price, which has traded between €55 and €100 per tonne of CO2 since 2023. The full compliance phase begins in 2026, when importers will face a financial obligation equal to the carbon price paid in the country of origin, minus any carbon price already paid there.
The UK CBAM, announced in December 2023, will apply to imports of iron and steel, aluminium, cement, ceramics, glass, hydrogen, and fertilisers. The UK government has indicated that the price will be linked to the UK ETS, which has traded at a discount to the EU ETS — typically £35 to £50 per tonne in 2024. The UK mechanism is scheduled to take effect in 2027, giving exporters a longer lead time than the EU regime.
Japan’s GX League is a voluntary carbon pricing system launched in 2023, covering approximately 50 per cent of Japan’s industrial emissions. Participating companies set their own emissions reduction targets and trade allowances within the league. The Japanese government has announced plans to introduce a mandatory emissions trading system by 2026 and a carbon surcharge on fossil fuel imports by 2028. Unlike the EU and UK mechanisms, Japan’s approach does not currently apply a border adjustment to imports, though the government has signalled that it may introduce one if trading partners do not adopt equivalent carbon pricing.
Why It Matters
For mid-market exporters, the divergence between these regimes creates three immediate problems. First, compliance costs multiply because each jurisdiction requires separate reporting, verification, and certificate purchasing processes. Second, the carbon price differential — currently higher in the EU than in the UK or Japan — means that exporters selling into multiple markets cannot apply a single carbon cost across their entire export portfolio. Third, the absence of mutual recognition agreements between the three regimes means that carbon credits or certificates purchased in one jurisdiction are not transferable to another.
A mid-market steel fabricator exporting to all three markets, for example, must track embedded emissions per product line, report separately to each regulator, and purchase certificates at three different price levels. The administrative burden alone is estimated by trade associations to add 2–5 per cent to compliance costs for companies that lack dedicated sustainability teams.
How Mid-Market Exporters Are Preparing
Interviews with trade bodies and advisory firms indicate that mid-market exporters are adopting three broad strategies.
Strategy one: internal carbon accounting. Companies are investing in software platforms that track emissions at the product level, rather than at the facility level. This is necessary because CBAM requires importers to declare the actual embedded emissions of each shipment, not an average. Providers such as CarbonChain, Plan A, and Normative have reported increased demand from mid-market manufacturers in the EU and UK since early 2024.
Strategy two: supply chain reconfiguration. Some exporters are shifting production to countries with lower carbon intensity or to jurisdictions where carbon pricing is already in place. For example, Turkish steel producers have increased exports to the EU in 2024, partly because Turkey has its own ETS that reduces the CBAM liability for Turkish-origin steel. Mid-market exporters without production flexibility are instead negotiating with suppliers to provide low-carbon inputs, such as green hydrogen or recycled scrap, to reduce embedded emissions.
Strategy three: voluntary carbon credit purchases. In Japan, where the GX League is voluntary, some mid-market exporters are purchasing carbon credits to demonstrate early compliance and to prepare for the expected mandatory system. However, the quality and price of credits vary widely, and there is no standardised verification framework across the three regimes.
Commercial Impact
The commercial impact of divergent carbon pricing is most acute in sectors with high carbon intensity and thin margins: steel, aluminium, cement, and fertilisers. For a mid-market aluminium extruder exporting to the EU, the CBAM cost could add 3–8 per cent to the landed cost of goods, depending on the carbon intensity of the production process and the EU ETS price at the time of import. In the UK, the equivalent cost is likely to be lower, at 2–5 per cent, given the lower UK ETS price. In Japan, there is currently no border adjustment, so the cost is zero — but this advantage may disappear if Japan introduces its own CBAM by 2028.
This price differential creates an incentive for exporters to prioritise sales to markets with lower carbon costs, potentially distorting trade flows. However, the effect is likely to be modest in the short term because transport costs, tariffs, and customer relationships remain the dominant factors in export decisions.
Risks / Unknowns
Several uncertainties remain. First, the EU and UK have not agreed on mutual recognition of carbon pricing, meaning that a UK exporter selling into the EU may face double counting of carbon costs. Second, the UK CBAM’s scope is broader than the EU’s, covering ceramics and glass, which will affect exporters in those sectors who are not currently subject to carbon pricing in their home markets. Third, Japan’s transition from voluntary to mandatory carbon pricing is not yet legislated, and the timeline could slip if the ruling Liberal Democratic Party faces political opposition from industrial groups.
There is also the risk of retaliatory trade measures. The EU CBAM has been criticised by China, India, and Brazil as a form of green protectionism. If the World Trade Organization rules against the mechanism, the entire framework could be disrupted. Mid-market exporters should therefore avoid making irreversible investments based solely on the current regulatory trajectory.
FY Outlook
Over the next 12 to 24 months, we expect three developments. First, the EU will begin full CBAM enforcement in 2026, which will force mid-market exporters to either absorb the cost or pass it on to customers. Second, the UK will finalise its CBAM legislation, likely with a price floor to prevent carbon leakage. Third, Japan will move towards mandatory carbon pricing, though a full border adjustment is unlikely before 2028.
For mid-market exporters, the most prudent strategy is to invest in product-level carbon accounting now, regardless of which regime applies. The data required for CBAM compliance is also useful for voluntary reporting frameworks such as the Task Force on Climate-related Financial Disclosures (TCFD) and the International Sustainability Standards Board (ISSB), which are increasingly demanded by investors and large corporate buyers.
Conclusion
The divergence between the EU, UK, and Japanese carbon border adjustment mechanisms is not a temporary anomaly. It reflects deeper differences in political economy, industrial structure, and climate ambition. Mid-market exporters that treat carbon compliance as a strategic function — rather than a regulatory afterthought — will be better positioned to manage cost volatility, access low-carbon supply chains, and maintain market access across all three jurisdictions. Those that delay risk being priced out of the EU market by 2026 and facing similar pressure in the UK by 2027.
Source Notes
This analysis draws on publicly available policy documents from the European Commission, the UK Department for Energy Security and Net Zero, and Japan’s Ministry of Economy, Trade and Industry. Trade association briefings from the Confederation of British Industry, the European Steel Association, and the Japan Iron and Steel Federation have informed the assessment of mid-market exporter responses. No proprietary data or confidential interviews were used. All carbon price ranges are based on observed market data from the EU ETS, UK ETS, and GX League as of mid-2024. Specific compliance cost estimates are illustrative and based on industry averages; actual costs will vary by company and product.
