Three Central Banks Test Synchronised FX Settlement: What BOE, MAS, and BOT's Collaboration Means for Cross-Border Payments

In November 2025, three central banks - the Bank of England (BOE), the Monetary Authority of Singapore (MAS), and the Bank of Thailand (BOT) - announced a joint programme to explore synchronised foreign exchange settlement across borders. The experiments will test whether real-time, atomic payment-versus-payment (PvP) FX settlement can work across different RTGS systems, time zones, and regulatory frameworks.

This collaboration deserves more attention than it has received. If successful, it could offer a credible alternative to the CLS model for FX settlement risk elimination - one that works natively across central bank infrastructure rather than through an intermediary.

The Problem Being Solved

Foreign exchange settlement risk - the risk that one leg of an FX trade settles while the other does not - remains one of the most significant systemic risks in global finance. CLS Bank settles roughly $6.5 trillion per day in 18 currencies, but its coverage is far from universal. Many currency pairs, particularly involving emerging market currencies like the Thai baht, are not CLS-eligible.

For non-CLS currencies, the industry relies on correspondent banking arrangements where each leg settles independently - often across different time zones - creating settlement risk windows that can last hours or even days. The BIS estimated in 2022 that $2.2 trillion in daily FX trades still settle without any PvP protection.

The Synchronisation Approach

The BOE/MAS/BOT collaboration builds on Project Meridian FX, led by the BIS Innovation Hub London in partnership with the BOE, Bank of France, Deutsche Bundesbank, Bank of Italy, and ECB. Meridian demonstrated that a synchronisation operator could coordinate settlement across two different RTGS systems, ensuring both legs of an FX transaction settle simultaneously or not at all.

The new three-way collaboration extends this concept in important ways:

Real RTGS simulation: The experiments use simulated versions of each central bank's actual RTGS infrastructure - CHAPS (via the BOE's RTGS Renewal platform), MAS Electronic Payment System (MEPS+), and BAHTNET. This is not a theoretical exercise; it tests against real system constraints.

DLT and conventional hybrid: The experiments explore synchronisation across both conventional RTGS environments and distributed ledger technology-based settlement systems. MAS has been particularly active in DLT settlement through Project Ubin and its successor programmes.

Three-way, multi-timezone: Unlike bilateral experiments, this programme tests coordination across three jurisdictions in substantially different time zones (London, Singapore, Bangkok), testing the practical limits of synchronised settlement.

How It Differs from CLS

CLS operates as a trusted intermediary - banks pre-fund accounts at CLS Bank, which then simultaneously debits and credits the corresponding legs. This works well but requires CLS membership, CLS-eligible currencies, and adherence to CLS settlement windows.

Synchronised settlement, by contrast, aims to coordinate settlement directly across central bank RTGS systems without a central intermediary. The synchronisation operator acts as a coordinator, not a counterparty. This means:

No need to pre-fund accounts at a central utility

Settlement occurs on central bank money, not on the books of an intermediary Potentially applicable to any currency pair where both central banks participate No dependency on a single commercial entity for systemic risk mitigation

The Broader Context

This collaboration sits within a wider movement toward RTGS interoperability:

Project Nexus (now Nexus Global Payments) is connecting instant payment systems across jurisdictions for retail payments mBridge (now operated by member central banks after BIS exit) tested multi-CBDC wholesale settlement The ECB's Pontes project is connecting DLT-based settlement to Eurosystem infrastructure

The BOE/MAS/BOT programme occupies a different niche: it focuses on making existing RTGS infrastructure work together for FX settlement, without requiring new currencies (like CBDCs) or new centralised entities (like CLS).

What to Watch

Timeline: The initial experiments are underway. Results from the simulated RTGS testing phase are expected in 2026, though no firm date has been announced. Currency pairs: GBP/SGD and SGD/THB are likely candidates for initial testing, filling gaps in CLS coverage. BOE Synchronisation Lab: The Bank of England is separately launching a Synchronisation Lab in 2026 to test synchronisation messaging flows in a non-live environment - a programme that could feed directly into this collaboration. Scalability: The critical question is whether synchronised settlement can handle the volume and speed requirements of actual FX markets, not just controlled experiments.

What This Means for Practitioners

For treasury and payments teams at institutions with GBP, SGD, or THB exposures, this programme signals a potential shift in how FX settlement risk is managed for non-CLS currency pairs. It does not change anything today, but it establishes a direction of travel: central banks are investing in infrastructure that could make PvP settlement the norm rather than the exception.

For FX market infrastructure providers and CLS itself, the programme raises competitive questions. If central banks can coordinate PvP settlement directly, the case for intermediated models weakens - though CLS's scale and proven track record remain formidable advantages.

Sources: Bank of England - BOE, MAS and BOT to Explore Synchronised FX Settlement Across Borders; Monetary Authority of Singapore - BOE, MAS and BOT to Explore Synchronised FX Settlement Across Borders; Fintech News Singapore - UK, Singapore and Thailand Central Banks Collaborate on FX Settlement.