The aftermath of Brexit has produced few certainties and a great many questions, not least for those charged with tracking the movement of goods and services between the UK and the European Union. For analysts, policymakers, and supply chain professionals, the challenge is to move from broad narratives—“disruption,” “realignment,” “new corridors”—to concrete evidence. One of the most effective, if underutilized, tools for this purpose is the International Standard Industrial Classification (ISIC) system, when used to organize and interpret customs and trade data.
The premise is straightforward. Customs declarations on both sides of the Channel capture immense volumes of data on the movement of goods and services. When these flows are systematically aggregated and coded using ISIC—automotive parts under 2910, financial services under 6419—a clearer picture emerges of where, and how, supply chains are being reconfigured.
Start with automotive parts (ISIC 2910). The UK’s automotive sector, heavily integrated with EU suppliers and customers, has always depended on finely tuned cross-border logistics. By gathering customs data from both the UK’s HM Revenue & Customs and the EU’s Eurostat, and tagging all relevant transactions under ISIC 2910, one can compare the volume and value of parts moving between the UK and EU over time. The key is to construct a timeline that captures several years before and after 2021, when the UK’s formal departure from the EU trading bloc introduced new regulatory and logistical complexities.
The analysis is not merely a matter of absolute flows, but of patterns. Did imports of certain parts drop off sharply, only to recover via alternative suppliers outside the EU? Did exports to the continent decline, or did firms reroute through third countries to minimize frictions? Analysts can create before-and-after snapshots—annual or quarterly, as data allows—using ISIC-coded customs declarations. A shift in the origin or destination of parts, or an uptick in trade with new partners, signals a realignment of the supply chain.
Financial services (ISIC 6419) offer a different, though related, perspective. Here, trade is less about physical movement and more about flows of contracts, capital, and service provision. Nonetheless, trade in financial services is also tracked—through balance-of-payments statistics, service trade registries, and company-level disclosures—again assignable to ISIC codes. The question is not just how much total trade persists, but how the structure has changed. Are UK-based firms opening new offices in the EU? Has business moved to Dublin, Frankfurt, Paris, or other hubs, and what does the data reveal about the direction and value of these flows?
For those wishing to conduct their own analysis, a stepwise approach is helpful. Begin by compiling trade flow data, pre- and post-2021, disaggregated by ISIC code. Many public data sources exist, though firm-level data or proprietary datasets may offer additional granularity. Ensure consistency in code assignment—harmonizing UK and EU sources is essential, as differences in reporting standards can mask underlying shifts.
Once datasets are assembled, compare trade volumes, origins, and destinations for ISIC 2910 and ISIC 6419, respectively. Visualizing these changes—through charts, heat maps, or simple tables—often reveals corridors of trade that have diminished, emerged, or rerouted. Look, too, for timing: did shifts occur immediately after new trade rules took effect, or was there a lag as firms adapted? If new corridors are present—for example, increased automotive part imports from East Asia, or financial service exports redirected through EU subsidiaries—document the scale and persistence of these changes.
A complete analysis goes beyond just tallying numbers. Investigate qualitative data: industry association reports, company statements, or regulatory filings may explain why certain shifts occurred. Were they driven by tariffs, new customs checks, regulatory divergence, or simply the search for lower transaction costs? Combining ISIC-based quantitative analysis with contextual detail provides the most robust insight.
It’s important to acknowledge that not all changes are immediate or neatly captured in the data. Some firms hold back on reporting or restructure incrementally. Others may hedge by maintaining operations on both sides of the Channel. Over time, though, systematic monitoring using ISIC codes will reveal enduring patterns—allowing policymakers to calibrate responses, firms to adjust strategies, and researchers to move past speculation.
Ultimately, the promise of the ISIC framework is clarity: the ability to filter immense, noisy datasets into coherent, comparable evidence of supply chain adjustment. In the shifting landscape of post-Brexit trade, that clarity is more valuable than ever.