Pix, SEPA, BRICS and BIS: Four Paths Toward the Same Missing Layer

Why global instant payments fail not because of technology, but because settlement, governance and programmability remain structurally misaligned

Abstract

Despite significant advances in instant payment systems, tokenisation and digital asset infrastructures, global payments remain structurally fragmented. While execution speeds have increased markedly, settlement finality, governance and programmability continue to be addressed in isolation rather than as integrated components of a coherent financial architecture. This fragmentation becomes particularly visible as payment processes move towards real-time, event-driven and increasingly automated models in global trade and treasury operations.

This article examines four prominent approaches to modern payment infrastructure: Brazil’s Pix, Europe’s SEPA, emerging BRICS cross-border initiatives and the Bank for International Settlements’ experimental projects, not as competing systems, but as partial solutions optimising different layers of the payment stack. Each addresses specific challenges, ranging from domestic execution efficiency to regional standardisation and wholesale settlement in central bank money. None, however, provides an end-to-end framework that aligns execution, settlement finality, governance and programmability across jurisdictions.

By analysing these initiatives through a layered architectural lens, the article argues that the central challenge of global instant payments is no longer technological capability, but institutional coordination and settlement design. It proposes that sustainable innovation in global payments requires the integration of programmable processes with interoperable settlement layers anchored in central bank money, supported by open governance and legally robust finality. In this context, the debate shifts from the optimisation of individual rails to the design of shared infrastructure capable of supporting real-time global trade.

Introduction

Over the past decade, the global payments landscape has undergone a remarkable acceleration. Instant payment systems, real-time treasury operations, tokenised assets and digital settlement experiments have moved from conceptual pilots to operational reality in multiple regions. Yet this apparent progress masks a deeper structural tension. While payments are increasingly executed in real time, the underlying settlement, governance and legal finality mechanisms remain fragmented, jurisdiction-bound and inconsistently integrated. The result is a global payments environment that is faster, but not fundamentally more coherent.

This tension is becoming increasingly visible as global trade and corporate finance adopt event-driven and programmable operating models. Execution speed alone is no longer sufficient. As payment processes automate and scale across borders, the question shifts from how quickly money moves to when, where and under which authority value is finally settled. It is at this architectural level, rather than at the level of individual products or political narratives, that today’s debates around instant payments, central bank digital currencies and alternative settlement networks must be examined.

This article approaches that examination by comparing four influential payment infrastructures, Pix, SEPA, emerging BRICS initiatives and BIS-led experiments, not as rivals, but as complementary attempts to address different layers of a shared problem.

Speed Is No Longer the Binding Constraint

For much of the past three decades, the evolution of payment systems has been framed primarily as a problem of speed and efficiency. Batch-based processing, limited operating hours and fragmented correspondent banking arrangements were widely identified as the principal bottlenecks in cross-border and domestic payments. Considerable institutional and technological effort was therefore directed towards accelerating execution, reducing cut-off times and improving straight-through processing.

These efforts have largely succeeded. A growing number of jurisdictions now operate domestic instant payment systems that provide near-real-time execution and immediate availability of funds to end users. Brazil’s Pix, Europe’s SEPA Instant Credit Transfer (SCT Inst), India’s UPI and similar systems demonstrate that real-time execution at scale is technically feasible, economically viable and socially impactful. From a purely operational perspective, the question of “how fast payments can move” has largely been answered.

However, the increasing prevalence of real-time execution has exposed a more fundamental limitation. Speed optimises only one layer of the payment process: execution. It does not, by itself, resolve questions of settlement finality, legal certainty, balance sheet exposure or cross-system interoperability. In fact, as execution accelerates, the weaknesses of underlying settlement arrangements become more pronounced rather than less relevant.

This distinction is particularly important in cross-border and multi-currency contexts. While instant payment systems can deliver rapid crediting of accounts, the ultimate settlement of obligations often continues to rely on deferred processes, commercial bank money and jurisdiction-specific legal frameworks. As a result, faster execution may coexist with persistent settlement risk, intraday liquidity pressures and fragmented governance structures.

From an architectural perspective, this implies that further gains in payment system performance cannot be achieved by execution-layer optimisation alone. Once speed ceases to be the binding constraint, attention must shift to the design and coordination of settlement mechanisms, governance models and the legal foundations of finality. It is at this level that contemporary initiatives increasingly diverge, and where meaningful comparison between systems such as Pix, SEPA, BRICS-linked proposals and BIS-led experiments becomes analytically productive.

Execution, Clearing and Settlement as Distinct Architectural Layers

A persistent source of confusion in contemporary payment debates arises from the tendency to treat execution, clearing and settlement as a single, homogeneous process. While closely related in operational terms, these functions represent analytically distinct layers within the payment architecture, each governed by different technical, legal and institutional logics.

Execution refers to the initiation and routing of a payment instruction and the conditional crediting of accounts. Modern instant payment systems have significantly optimised this layer, enabling near-immediate user-facing outcomes. Clearing, by contrast, concerns the calculation and netting of obligations between participating institutions. Settlement represents the final discharge of those obligations through the transfer of a settlement asset, thereby extinguishing counterparty claims and producing legal finality.

In traditional banking infrastructures, these layers are tightly coupled but not temporally aligned. Execution may occur within seconds, while clearing and settlement may follow hours or even days later, often across different systems and balance sheets. This decoupling has historically been managed through credit risk, liquidity buffers and legal constructs designed for batch-based environments.

As payment systems move towards real-time and continuous operation, this architectural separation becomes increasingly consequential. Accelerated execution compresses the time available to manage settlement risk, while automated processes reduce the scope for discretionary intervention. Under such conditions, the nature of the settlement asset and the legal framework governing finality assume heightened importance.

Commercial bank money, which dominates settlement in most existing systems, represents a private liability and therefore embeds counterparty risk by design. Central bank money, by contrast, constitutes a public settlement asset with unique properties of legal certainty, risk insulation and systemic trust. The distinction between these assets is not merely technical but foundational, as it determines how risk is distributed across participants and how resilient a system remains under stress.

An architectural analysis must therefore distinguish clearly between improvements at the execution layer and transformations at the settlement layer. While the former can deliver efficiency gains and enhanced user experience, only the latter can fundamentally alter the risk, governance and interoperability characteristics of a payment system. This distinction provides the analytical basis for assessing whether current initiatives represent incremental optimisation or structural innovation.

It is against this layered framework that domestic instant payment systems, regional standards and emerging cross-border settlement proposals must be evaluated. Their differences lie less in technological sophistication than in how, and whether, they address the settlement layer explicitly.

Domestic Instant Payment Systems as Execution-Layer Optimisations

Over the past decade, a growing number of jurisdictions have introduced domestic instant payment systems designed to modernise retail and business payments. These systems typically prioritise speed, availability and user experience, offering continuous operation, immediate confirmation and increasingly rich data exchange. From an execution perspective, they represent a significant departure from batch-oriented legacy infrastructures.

Architecturally, however, these systems are best understood as execution-layer optimisations rather than as comprehensive transformations of the payment stack. They focus on the rapid transmission and processing of payment instructions between participant institutions, often supported by enhanced messaging standards and real-time liquidity management. The user-facing outcome is near-immediate crediting, which materially improves cash-flow visibility and operational efficiency for end users.

Crucially, these improvements do not, in themselves, alter the underlying settlement logic. In most implementations, final settlement continues to rely on commercial bank money, with positions ultimately reconciled through deferred or periodic settlement processes. Even where prefunding or intraday liquidity mechanisms are employed, the settlement asset remains a private liability rather than a public one.

This distinction matters because execution speed and settlement finality are not interchangeable. Instant execution reduces operational friction but does not eliminate counterparty exposure. As long as settlement occurs outside central bank balance sheets, the system’s resilience depends on the creditworthiness and liquidity management of participating institutions, as well as on legal arrangements designed to manage failure scenarios.

From a systemic perspective, domestic instant payment systems therefore deliver substantial efficiency gains without fundamentally reconfiguring risk allocation. They improve how quickly value appears to move, but not how or where value is ultimately settled. This makes them highly effective within stable domestic environments, yet structurally limited when extended across borders, currencies or regulatory regimes.

The growing success of these systems can paradoxically obscure this limitation. High adoption rates and positive user experience create the impression of infrastructural completeness, even though the settlement layer remains unchanged. As long as payments remain predominantly domestic and low-risk, this architectural gap may appear tolerable. However, as real-time execution becomes the norm and payment flows increasingly span jurisdictions, the absence of an equally real-time, risk-free settlement layer becomes more pronounced.

Understanding domestic instant payment systems as optimisation layers rather than as full-stack solutions is therefore essential. It clarifies why further gains in speed and availability, while valuable, cannot by themselves address challenges of cross-border interoperability, systemic risk reduction and global scalability. These challenges reside not at the execution layer, but at the level of settlement architecture.

Why Cross-Border Extension Exposes the Limits of Execution-Only Models

The extension of real-time payment capabilities across borders introduces a set of structural challenges that execution-layer optimisation alone cannot resolve. While domestic instant payment systems benefit from legal harmonisation, shared currency frameworks and aligned supervisory regimes, these conditions rarely persist beyond national or regional boundaries.

Cross-border payments operate at the intersection of multiple currencies, legal systems, regulatory frameworks and liquidity regimes. Execution speed in such environments does not simply amplify efficiency; it amplifies coordination problems. Each additional jurisdiction introduces new settlement calendars, risk thresholds, compliance requirements and failure modes, which cannot be neutralised by faster messaging or improved user interfaces alone.

In execution-only architectures, cross-border connectivity is typically achieved through bilateral or hub-based linkages between domestic systems. These arrangements focus on routing payment instructions and managing prefunding or liquidity bridges between participants. While such approaches can reduce friction at the margins, they leave the fundamental settlement logic unchanged. Obligations continue to be settled in commercial bank money, often across multiple balance sheets and time zones.

This creates a structural asymmetry: execution becomes real-time, while settlement remains fragmented, deferred and risk-bearing. As a result, credit and liquidity risk are not eliminated but redistributed, often in opaque ways. The faster the execution layer operates, the more sensitive the system becomes to settlement disruptions, liquidity bottlenecks and legal uncertainty.

Furthermore, execution-only cross-border models tend to rely on conditional guarantees, bilateral credit lines or collateralisation schemes to manage risk. These mechanisms introduce complexity and cost, and they scale poorly as the number of participants and corridors increases. What appears manageable in limited pilot corridors becomes increasingly brittle when extended to global networks.

From an institutional perspective, this exposes a deeper limitation. Cross-border payments are not merely technical exchanges between systems; they are legal and economic events that require universally recognised finality. Without a shared settlement asset that is trusted across jurisdictions, execution-layer connectivity cannot produce true interoperability. It can only simulate immediacy while deferring risk resolution.

The consequence is a proliferation of partially connected networks rather than a coherent global infrastructure. Each linkage optimises locally, but the system as a whole remains fragmented. This fragmentation is not accidental; it reflects the absence of a settlement layer capable of operating across borders with uniform legal certainty and risk neutrality.

Cross-border extension thus acts as a stress test for execution-only models. It reveals that speed, availability and user experience, while necessary, are insufficient conditions for global scalability. The binding constraint is not how fast instructions move, but how and where value is ultimately settled.

The Settlement Asset as the Missing Variable in Global Scalability

The structural limitations identified in cross-border execution-only models ultimately converge on a single, often underexplored variable: the nature of the settlement asset itself. While execution systems determine how payment instructions are transmitted and processed, it is the settlement asset that determines whether obligations are discharged with legal certainty, risk neutrality and systemic trust.

In most existing payment architectures, settlement relies on commercial bank money. This asset represents a private liability, issued by individual institutions and embedded within their balance sheets. While commercial bank money functions efficiently within established domestic frameworks, its suitability diminishes as payment processes become continuous, automated and cross-border by design. The resulting exposure to credit, liquidity and legal risk does not disappear with faster execution; it becomes more immediate and more tightly coupled to system stability.

Global scalability requires a settlement asset that is universally recognised, legally final and institutionally neutral. Central bank money uniquely fulfils these criteria. It constitutes the ultimate settlement asset within a currency area, free from private credit risk and anchored in public law. Historically, access to central bank settlement has been restricted to regulated financial institutions, reflecting the batch-oriented nature of legacy infrastructures and the need to manage systemic risk through controlled participation.

As payment processes evolve towards real-time operation, this historical separation between execution innovation and settlement architecture becomes increasingly untenable. Automated, condition-based transactions require deterministic settlement outcomes. Without a settlement asset that can support continuous finality, programmability at the execution layer merely accelerates the accumulation of contingent claims.

This observation reframes the debate around payment modernisation. The central challenge is not how to connect execution systems more efficiently, but how to anchor those systems to a settlement layer capable of operating at the same temporal and legal resolution. Without such anchoring, global interoperability remains fragile, dependent on bilateral arrangements and risk mitigation techniques that do not scale.

The settlement asset therefore functions as the gravitational centre of the payment architecture. It determines not only risk distribution, but also governance, access and trust. Any attempt to construct globally interoperable payment infrastructures without addressing this layer will inevitably reproduce fragmentation at higher speeds.

Recognising the settlement asset as a design variable rather than a given marks a conceptual shift. It opens the analytical space for institutional innovation at the infrastructure level, rather than continued optimisation within inherited constraints. This shift provides the foundation for understanding why recent initiatives increasingly focus on settlement itself, rather than solely on execution efficiency.

Institutional Responses to the Settlement Constraint

Once the settlement asset is recognised as the limiting factor in global payment scalability, recent institutional initiatives can be reinterpreted not as isolated experiments, but as convergent responses to a shared architectural problem. Across jurisdictions and governance models, a growing number of actors are exploring ways to reintroduce central bank money as an active settlement layer capable of supporting real-time, cross-border processes.

At the multilateral level, initiatives coordinated by international institutions have focused explicitly on settlement interoperability rather than on execution efficiency. Experimental platforms exploring multi-currency settlement, shared ledgers and synchronised settlement mechanisms reflect a recognition that global payments cannot be stabilised through bilateral optimisation alone. These projects treat settlement finality as a public good, requiring coordination across central banks rather than competition between private intermediaries.

Parallel to these efforts, several emerging market economies and regional blocs have begun to articulate settlement infrastructures aimed at reducing dependency on correspondent banking chains and dominant reserve currencies. While often framed in geopolitical terms, these initiatives are more coherently understood as attempts to regain control over settlement finality and liquidity management in cross-border trade. Their common feature is not political alignment, but the explicit use of central bank money as the settlement anchor.

Within advanced economies, central bank digital currency initiatives represent a complementary response. While many early discussions have focused on retail use cases, the underlying architectural implication is broader. By making central bank money natively compatible with digital infrastructures, CBDCs reopen the question of how settlement access, programmability and interoperability can be designed for continuous operation. Importantly, this does not imply a displacement of private sector innovation, but a reconfiguration of its foundation.

These institutional responses share a critical characteristic: they shift the locus of innovation from the execution layer to the settlement layer. Rather than attempting to optimise existing commercial bank-based arrangements indefinitely, they seek to redesign the conditions under which settlement occurs. This marks a departure from incrementalism towards structural intervention at the infrastructure level.

At the same time, these approaches remain incomplete. Most initiatives address either wholesale or retail settlement in isolation, and few are yet integrated into corporate payment and treasury workflows. Nevertheless, they signal an emerging consensus: global payment systems cannot achieve real-time, programmable and interoperable operation without revisiting the role of central bank money in settlement.

Understanding these developments as architectural responses rather than ideological positions allows for a more constructive evaluation. It highlights convergence where public discourse often emphasises divergence, and it clarifies that the underlying objective is not control over execution, but stability, finality and trust at the settlement layer.

Synthesising Pix, SEPA, BRICS and BIS Within a Layered Framework

When examined through a layered architectural lens, the apparent diversity of contemporary payment initiatives becomes analytically coherent. Systems such as Pix, SEPA Instant, emerging BRICS-linked settlement efforts and BIS-coordinated projects do not represent competing visions of the future, but rather address different layers of the same structural problem.

Domestic instant payment systems, exemplified by Pix and SEPA Instant, operate primarily at the execution layer. They demonstrate that real-time payment initiation, continuous availability and high-volume processing can be achieved reliably within harmonised legal and currency environments. Their success lies in operational efficiency, user adoption and economic inclusion. However, their settlement logic remains anchored in commercial bank money, rendering them optimised yet incomplete from a global scalability perspective.

Cross-border initiatives associated with BRICS economies focus on a different constraint. Their primary objective is not execution speed for end users, but sovereignty over settlement and liquidity management in international trade. By emphasising settlement in central bank money and reducing reliance on correspondent banking chains and dominant reserve currencies, these efforts explicitly target the settlement layer. While often interpreted through geopolitical narratives, architecturally they address the same deficiency identified in execution-only models: the absence of a universally trusted settlement anchor.

BIS-led initiatives occupy a distinct but complementary position. They do not aim to create production payment systems, but to explore interoperable settlement architectures across currencies and jurisdictions. By experimenting with shared settlement platforms, synchronised settlement mechanisms and multi-currency coordination, these projects explicitly treat settlement as a design problem rather than an inherited constraint. Their value lies less in immediate deployment and more in defining architectural primitives for future systems.

Viewed together, these initiatives illustrate a fragmented but converging trajectory. Execution-layer optimisation, regional standardisation and settlement-layer innovation are progressing in parallel, but largely without integration. Each addresses a necessary condition for global instant payments, yet none alone provides a sufficient solution. The absence of a unifying architectural framework explains why debates often oscillate between domestic efficiency, monetary sovereignty and technological experimentation without resolving their interdependence.

This synthesis suggests that the current landscape should not be interpreted as a competition between models, but as an incomplete assembly of layers. The challenge lies not in selecting a single approach, but in designing interfaces between them that preserve their respective strengths while addressing their limitations.

Toward a Coherent Architecture for Global Instant Payments

A coherent global instant payment architecture cannot be achieved through further optimisation at individual layers alone. Nor can it emerge from isolated institutional initiatives, however sophisticated. What is required is an explicit architectural alignment between execution, clearing and settlement, supported by governance structures capable of operating across jurisdictions.

At the execution layer, systems must support real-time, programmable and data-rich payment initiation. This capability is already largely in place. At the settlement layer, value transfer must occur in assets that provide legal finality, systemic trust and neutrality across borders. Central bank money, whether accessed through existing infrastructures or digitally native representations, remains uniquely positioned to fulfil this role.

Crucially, programmability should be understood as a property of processes, not of money itself. Payment logic, compliance rules and conditional execution belong in systems and applications. Finality belongs in the settlement asset. Conflating these functions risks either undermining trust or constraining innovation. A coherent architecture must therefore separate concerns while ensuring deterministic interaction between layers.

From an institutional perspective, this implies a redefinition of roles. Central banks act as infrastructure providers and guarantors of settlement integrity, not as competitors in product markets. Private institutions innovate at the execution and service layers, building differentiated offerings on top of shared settlement foundations. International coordination bodies provide the standards and interfaces necessary for interoperability.

The transition to such an architecture will be incremental rather than revolutionary. It will require bridging domestic instant payment systems to interoperable settlement layers, integrating wholesale and retail perspectives, and aligning regulatory frameworks with architectural realities. Yet the direction is clear. As payment processes become real-time and programmable, settlement finality can no longer remain deferred, fragmented or opaque.

The future of global instant payments will not be defined by the fastest execution rail, the most sophisticated token or the loudest political narrative. It will be defined by the ability to align speed with finality, innovation with trust, and domestic efficiency with global interoperability. Designing that alignment is no longer a theoretical exercise. It is the next structural challenge for the global financial system.

Conclusion

Viewed through the lens of Global Instant Payments, the developments discussed in this article point to a common architectural requirement rather than divergent institutional agendas. The RELEVANT framework, Regulatory, Economic and Legal Enablement through Value Alignment and Networked Trust, provides a way to integrate execution efficiency, settlement finality and governance coherence into a single analytical construct. It emphasises that sustainable innovation in payments does not arise from isolated optimisation, but from aligning technological capability with legal certainty and institutional trust at scale. In this sense, GIP is not a call for faster payments alone, but for an infrastructure in which real-time execution and central bank settlement operate as complementary layers, enabling programmable, resilient and globally interoperable financial processes.

Pix, SEPA, BRICS and BIS: Four Paths Toward the Same Missing Layer was originally published in Coinmonks on Medium, where people are continuing the conversation by highlighting and responding to this story.