From SIU to T+1: Transforming Post-Trade Settlement in Europe

Lessons from North America’s T+1 Settlement Transition 

The North American experience offers a vivid proof point. On May 28, 2024, the United States, Canada and Mexico compressed their settlement cycle from T+2 to T+1. Clearing-fund requirements at the National Securities Clearing Corporation (NSCC) fell by more than 20%,¹ freeing up capital for new lending channels and innovation. Firms also discovered that automation and higher data-quality standards — necessary to meet the accelerated timelines — translated into material reductions in counterparty risk and funding costs, especially during times of market stress. Europe, the United Kingdom and Switzerland have watched these results closely and drawn two lessons: First, the benefits are real; second, the rush to meet a go-live date in North America sometimes forced tactical, just-in-time fixes rather than strategic overhauls. Their joint transition — now slated for October 11, 2027 — must therefore be more deliberate and resilient. 

U.K.’s Strategic Approach to Implementing T+1 Settlement 

In the U.K., the Accelerated Settlement Taskforce (AST) convened in December 2022 under chair Andrew Douglas. Its March 2024 Geffen Report recommended a move to T+1 before the end of 2027, and by early 2025, the AST’s technical group had issued an Implementation Plan, complete with a detailed Code of Conduct. This Code categorizes actions into “Critical,” “Highly Recommended” and “Post-Trade Environment” buckets, ensuring that all exchange-executed transactions settle in one day, while carving out sensible exemptions for over-the-counter (OTC) trades, primary issuances and select securities financing transactions. Concurrently, Euroclear UK & International is modernizing its CREST platform, aligning system upgrades with the October 11, 2027 go-live date to guarantee that backbone technology evolves in lockstep with market practices. 

EU’s Roadmap for T+1 Securities Settlement

Brussels embarked on a parallel path. In October 2024, an EU industry task force released an initial High-Level Roadmap for T+1 and the European Securities and Markets Authority (ESMA), the European Commission, and the European Central Bank (ECB) issued a joint statement announcing plans to establish a governance structure for an EU move to T+1. By February 2025, proposed amendments to the Central Securities Depositories Regulation (CSDR) were on the table, and by mid-year, an EU T+1 Industry Committee with 12 dedicated workstreams issued a detailed “High-level Roadmap to T+1 Securities Settlement in the EU,” which was open for public consultation until August 2025. As co-lead of the Scope workstream, BNY is advising on which asset classes and transaction types should migrate, where exemptions are appropriate and how to handle complex activities such as securities financing and certain types of derivatives trading. The roadmap envisions a staged preparation: FAQs in Q1 2026, a formal testing plan by Q2 (possibly aligned with the U.K. roadmap), full system implementations through 2026 and end-to-end dress rehearsals in Q1 2027 before the October launch. 

Switzerland’s Commitment to Harmonized T+1 Settlement 

Switzerland committed to the same October 11, 2027 date. Its Securities Post-Trade Council published T+1 recommendations in September 2025,² thereby ensuring that Geneva and Zurich remain fully interoperable with EU and U.K. partners and continue to serve as premier hubs for cross-border business. 

How SIU and T+1 Settlement Enhance Cross-Border Trades 

Together, the SIU and a harmonized T+1 regime unlock more than simply faster settlement. They create a foundation for standardized messaging, unified cut-off times and streamlined Settlement Standing Instructions — transformations that make cross-border trades nearly as seamless as domestic ones. As data quality and straight-through processing become universal, custodians and central securities depositories (CSDs) will coordinate more effectively on securities data, corporate-action feeds and place-of-settlement fields. In turn, these improvements will foster trust in a single market and entice fresh waves of investment.

This post-trade overhaul also lays the groundwork for innovation. Real-time collateral management, tokenized asset issuance platforms and atomized liquidity pools spanning multiple CSDs move from theory to reality once settlement becomes near-instantaneous and pan-European in scope. Far from being merely a dry regulatory exercise, the SIU–T+1 nexus will serve as a launchpad for next-generation market infrastructure — reshaping not only how trades settle, but how capital is sourced, allocated and ultimately put to work. 

Challenges in Implementing T+1 Settlement Across Europe

The path ahead is not without challenges. Europe’s mosaic of 27 member states, over 30 CSDs and a dozen Central Counterparties (CCPs) demands governance of exceptional complexity. Any misalignment — whether in cut-off times, auto-splitting settings or Settlement Standing Instructions — can ripple through the chain and undermine one-day finality.  

BNY’s Role in Supporting the T+1 Settlement Transition 

From advising on data-quality standards and system upgrades, to co-designing industrywide testing frameworks and playbooks, BNY is helping clients, counterparties and infrastructure providers navigate each phase of the journey. A harmonized T+1 settlement cycle promises to unlock a new chapter of cross-border growth for Europe’s capital markets. 

Ben Pott is the International Head of Public Policy & Government Affairs, BNY. Roberto De Paolis, Direct Markets Director, BNY and Christos Ekonomidis, Enterprise Transformation Senior Director, BNY also contributed to this article.

_{¹  "DTCC Comments on Industry’s T+1 Progress," Depository Trust & Clearing Corporation, May 30, 2024, https://www.dtcc.com/news/2024/may/30/dtcc-comments-on-industrys-t1-progress}

_{²  "Switzerland committed to the same October 11, 2027 date", Securities Post -Trade Council, September 12, 2025, https://www.six-group.com/dam/download/sites/swiss-sptc/t1/swiss-sptc-t1-recommendations-paper.pdf}