Why APIs Are Central to Cross-Border B2B Payments

Cross-border B2B payments represent a massive market that is projected to reach $47.8 trillion by 2032. 

Yet, as banks’ corporate clients demand faster, cheaper payouts to suppliers, contractors and platforms worldwide, the infrastructure behind those payments is showing its age.

What was once largely a bank-to-bank process now involves local clearing systems, real-time payment networks, mobile wallets and multiple payout methods. As businesses have to manage increasingly fragmented payment ecosystems, APIs are leading a shift away from static banking workflows toward programmable infrastructure that connects banks, payment networks, compliance processes, and treasury operations through a common interface.

This article explores how APIs are reshaping B2B payments and why they are becoming an important part of modern global payment infrastructure.

Table of contents

Why traditional B2B payment infrastructure is struggling

As cross-border payment volumes grow, business payments have to cover a wider range of markets, currencies, systems, and regulatory environments than ever before.

For banks and their clients’ finance and treasury teams, this becomes more difficult to manage at a global scale, in part due to common sources of friction:

• Shrinking correspondent networks – de-risking has cut correspondent relationships sharply over the past decade, leaving banks (especially smaller ones) with fewer routes and higher costs.
• Nostro liquidity trapped across multiple correspondent accounts.
• Long, opaque payment chains with limited end-to-end visibility for the bank’s clients.
• Slow, bilateral onboarding: every new corridor means a new RMA relationship, due diligence cycle, and ongoing monitoring burden.
• No native route to non-bank endpoints – wallets, stablecoins, local RTP schemes – that clients increasingly want to pay into.
• Competitive pressure from API-native fintechs winning the bank’s own B2B flows.

What makes this particularly challenging is that these issues don’t exist in isolation. A single cross-border payment can involve multiple financial institutions, currencies, compliance checks, settlement processes, and payout methods before funds reach the recipient.

Many traditional cross-border payment models were not designed for this level of complexity.

How APIs are connecting global payment networks

To operate at a global scale, banks need simplified access to multiple payout options rather than a single payment rail. Here, interoperability is not a value-add as much as a basic line of defence against competitors.

These include:

• Correspondent banking networks
• Local clearing systems
• Mobile wallet ecosystems
• Stablecoin wallets
• Real-time payment (RTP) networks
• Regional payment rails

Each of these payment environments operates with its own standards, settlement processes, connectivity requirements, and regulatory considerations. 

As banks are extending payout reach for clients, coordinating payments across multiple systems can quickly become a bottleneck, especially when different payout methods must be supported within a single payment operation.

Why interoperability is the key

Historically, supporting these environments required corridor-specific integrations, multiple banking relationships, and separate operational processes for different markets and currencies. 

Building these one by one and managing them individually increases the risk of issues during the payment flow. As payment ecosystems become more diverse, this DIY model can reach a breaking point.

Businesses need infrastructure that can coordinate across different payment systems while maintaining a consistent operational framework. This is where interoperability becomes the foundational key.

Without it, every new market, payout method, or payment network introduces additional operational overhead and patchwork fixes, creating more complexity and risk for finance, treasury, and payment teams.

How APIs support interoperability

If interoperability is the business outcome, APIs are the mechanism that helps deliver it.

Instead of building and maintaining separate integrations for individual corridors, APIs provide a standardised point of entry that lets businesses access multiple payment networks, and the optionality they need to operate rapidly and with agility.

In a way, an API connection can make interoperability “plug and play,” providing a solution layer that offers:

• Orchestration
• Connectivity
• Automation

These features make it easier for businesses to support new markets and payout methods as payment or business requirements evolve, because there’s no need to build new relationships or partnerships or tap into third parties and local institutions. 

These capabilities become particularly relevant as wallet-first ecosystems and real-time payments continue to expand in emerging markets, increasing the range of payment options businesses must support. 

API-driven payments can help businesses scale globally

The benefits of API-driven payment infrastructure extend beyond connectivity. By reducing fragmentation across payment systems, APIs can help businesses streamline payment operations as they expand into new markets.

The impact can be seen across a range of B2B payment use cases.

Extending corridor coverage without bilateral agreements

A regional or mid-tier bank looking to expand its cross-border payout coverage has traditionally faced a slow, bilateral process: identifying correspondent partners in each market, completing due diligence, establishing RMA relationships, and maintaining ongoing monitoring for every connection.

With API connectivity to an established network, a single integration can unlock payout capability across many countries. Banks can extend coverage for their clients without building and managing dozens of individual correspondent relationships, shortening go-to-market timelines from years to months.

Reaching beyond traditional bank accounts

Corporate clients increasingly need to pay contractors, gig workers, and suppliers in markets where bank transfers are slow, expensive, or simply not the recipient’s preferred method. Mobile wallets and stablecoin wallets are often faster and more accessible, particularly across emerging markets.

API-driven infrastructure allows banks to route payments to these non-bank endpoints through the same connection that handles traditional account payouts. This lets banks serve client demand for alternative payout methods without building separate integrations for each wallet ecosystem or rail.

Competing for SME cross-border flows

Smaller-ticket B2B payments are an area where banks have steadily lost ground to API-native fintechs, whose speed and pricing often outcompete traditional correspondent routes. For many banks, these flows leave quietly, one SME client at a time.

By routing payments through API-connected networks rather than long correspondent chains, banks can offer the speed, cost, and transparency that SME clients now expect, and defend a segment of cross-border business that would otherwise migrate to non-bank providers.

Strengthening compliance and oversight

Cross-border payments expose banks to direct regulatory obligations across every jurisdiction they touch, from sanctions screening to transaction monitoring and reporting. Managing these requirements across fragmented correspondent chains adds cost and risk.

API-driven workflows allow compliance checks, payment data, and reporting to move through a single, consistent framework. This gives banks clearer end-to-end visibility over payment journeys and helps embed regulatory controls directly into the payment flow rather than bolting them on afterwards.

How Thunes supports API-driven B2B payments

For global expansion to succeed, businesses need a way to connect to multiple payment systems without increasing operational headaches.

Thunes addresses this challenge with its API-accessible Direct Global Network.

One API, multiple payment ecosystems

Cross-border B2B payments increasingly need to support a mix of bank accounts, local payment systems, real-time payment networks, mobile wallets, and stablecoin wallets.

With a single API connection to the Thunes Direct Global Network, banks can access a broad range of global payment endpoints through one integration that replaces the need to build and maintain bilateral correspondent relationships. This includes connectivity across 140 countries, 90 currencies, 8 billion bank accounts, 4 billion mobile wallets, 500 million stablecoin wallets, and a network of more than 720 Members.

With this unrivaled access to markets and payment options, businesses can simplify expansion into new markets while supporting local payment preferences and payout requirements.

Connecting through existing Swift infrastructure

For many banks, the question is not whether to modernise cross-border payments but how to do so without ripping out existing infrastructure. Thunes addresses this by making its network accessible through the Swift connectivity banks already have. Through its Pay-to-Banks solution, the 11,000 financial institutions on the Swift network can route payments into the Thunes Direct Global Network with no additional technical integration, reaching bank accounts in over 130 countries in real time.

This access extends beyond traditional accounts. Thunes’ Pay-to-Stablecoin-Wallets solution is also available to Swift-connected banks, enabling real-time payouts to more than 500 million stablecoin wallets in over 140 countries. In practice, this gives banks the option to begin offering faster payouts and alternative payment methods immediately through Swift, then move to a direct API integration when deeper functionality or higher volumes justify it.

Built for global payment operations

Connectivity is only one part of cross-border payments. Businesses also need to coordinate compliance, payment routing, FX handling, and payout execution across multiple jurisdictions.

Through its Fortress Compliance Platform and SmartX Treasury System, Thunes helps embed these operational requirements into payment flows. 

• SmartX Treasury System supports liquidity and FX coordination across markets, helping businesses manage cross-border payment flows and multi-currency operations more efficiently.
• Fortress Compliance Platform embeds compliance controls directly into payment flows, helping businesses support international payment operations across multiple regulatory environments.

By combining API connectivity with multi-rail access and global interoperability, Thunes helps businesses build cross-border payment operations that can scale across markets without adding the complications traditionally associated with international payments.

APIs are the new foundation of modern B2B payments

Cross-border B2B payments are becoming more complex as businesses operate across a growing mix of payment systems, currencies, and regulatory environments. 

APIs are helping address this by connecting fragmented payment ecosystems through a more scalable and interoperable model. As payment networks continue to diversify, this connectivity becomes increasingly important for supporting global growth.

Through its Direct Global Network, Thunes helps businesses access multiple payment rails, local payment systems, and global payout capabilities through a single integration.

Contact us to learn how Thunes supports API-driven cross-border B2B payments through its Direct Global Network.