Why modernizing ACH is critical for faster payments

Deepak Gupta is chief product, engineering, and delivery officer at Volante Technologies, a financial technology company that helps banks modernize payments and financial infrastructure.

The ACH network processed over 1 billion Same Day ACH payments in 2025, totaling nearly $4 trillion. And in the first quarter of 2026 alone, there were over 403 million Same Day payments. When compared to Q1 2025, this accounts for a 23.6% increase in volume and a 22.1% value increase. Even more impressive, current volumes are on track to rise 60% year over year by the end of 2026, evidence that the ACH network is evolving beyond its traditional batch-processing roots toward near-real-time payments.

Rising consumer and business demand for faster payments is accelerating this transition, with two thirds of U.S. businesses likely to adopt instant payments, including The Clearing House’s RTP and Federal Reserve’s FedNow services, if given the opportunity. Yet, even as real-time rails and next-generation digital assets dominate the payments conversation, ACH remains an essential building block of the broader payments ecosystem. 

ACH is not disappearing, but the systems behind it are not keeping pace with modern payment demands. As demand for faster payments grows, many institutions still rely on infrastructure designed for overnight processing. Payment speeds and volumes are rising. Banks need ACH systems that can keep up and respond to fraud more effectively.

In many cases, ACH remains a preferred rail because of its ubiquity, cost profile, operating familiarity, and ability to support high-volume payment flows. Financial institutions must be able to support compressed processing windows, faster exception handling, improved fraud controls, and more resilient operations without abandoning the rail that still carries much of the country’s payment activity.  

However, despite both its increased demand and competitive functionality, ACH modernization still lags behind the realities of how transactions actually flow.

Cash and checks still accounted for one third of 2024 B2B transaction volume. This reliance on traditional payment methods exposes a gap. Core transaction systems, including ACH, are not advancing at the speed of current expectations, and banks cannot fully leverage faster payment capabilities without reworking the platforms that support them. Given that the ACH network processed 35.2 billion payments in 2025, newer real-time rails like FedNow and RTP cannot absorb this entire transaction volume. As a result, adapting ACH to support near-real-time capabilities is no longer optional; it is central for future growth. 

Fully utilizing Same Day ACH capabilities requires financial institutions to modernize platform infrastructure beyond traditional overnight batch execution models. While Same Day ACH still operates within ACH settlement and processing boundaries, unlike true real-time rails such as FedNow or RTP, it significantly compresses processing, fraud detection, exception handling, liquidity management, and operational response timelines compared to traditional next-day ACH. This starts with understanding how ACH has evolved and how the surrounding legacy architecture has introduced structural limitations around scalability, resiliency, operational agility, and continuous processing.

Evolving beyond batch processing origins

ACH started as a bulk-payment infrastructure that banks used to process large volumes of low-value payments, including payroll, utility bills, and other business transactions. These functions established ACH as a core banking function for decades, even as newer payment rails emerged. It traditionally followed overnight batch-processing cycles and predictable settlement windows, creating specific times when organizations could send or process payments.

As demand for faster payments has increased, ACH has shifted toward near-real-time functionality, enabling time-sensitive payment scenarios such as payroll corrections and urgent bill payments. Yet the platforms that run these transactions have fallen behind. Unlike RTP and FedNow, which were built from the ground up with real-time transactions in mind, legacy ACH operating models introduce structural constraints that limit scalability and flexibility. 

Faster payments meet legacy infrastructure

Traditional ACH batch architecture suffers from delayed settlements, complex customization requirements, and costly maintenance. Financial teams must manually intervene to manage these environments, which is not always possible due to operational demands and limited administrative bandwidth. 

Same Day ACH also introduces operational demands that many legacy ACH environments were not designed to support, including the need to prioritize Same Day processing over standard next-day batches, consistently meet strict processing window SLAs, and absorb large transaction volumes submitted close to network cutoff times. 

This foundation makes scalability difficult to sustain at the level modern payment environments require. Banks have limited insight into payment procedures. They must handle exceptions manually, face operational silos, and lack support for ongoing processing. When financial institutions attempt to modify or update their current systems, they often trigger outages that disrupt transaction execution. These limitations create structural barriers to scale and show that incremental upgrades are no longer sufficient.

Avoiding ACH delays during this shift to near-real-time performance requires financial institutions to fundamentally reconfigure their architecture to keep pace. Rigid configurations do not just slow ACH down. They constrain an institution's ability to scale. That is why modernization efforts converge on the same architectural shifts, regardless of institution size or strategy. 

Paving the way for real-time payments

For many financial institutions, Same Day ACH also serves as a practical transition step toward broader real-time payment adoption. Before fully scaling RTP or FedNow participation, Same Day ACH allows institutions to strengthen operational resiliency, validate liquidity and funding management approaches, improve fraud response models, and adapt support and operational teams to faster payment execution cycles within a more controlled settlement framework.

Once operational maturity is achieved, financial institutions can progressively expand into RTP and FedNow adoption while enabling intelligent payment routing across rails, using Same Day ACH, RTP, or FedNow dynamically based on factors such as urgency, transaction value, operating windows, liquidity position, cost optimization, and customer experience requirements.

While not the only approach, this framework directly addresses the key ACH challenges that hinder financial institutions. It can help facilitate faster execution, flexible configuration, real-time risk mitigation, deployment versatility, resilient infrastructure, and improved operational control. By addressing complex legacy infrastructure, banks can prepare themselves for a near-real-time payments environment. 

Unlocking the full potential of same day ACH

ACH is not the limitation; the systems surrounding it are. Upgraded ACH processing environments can operate outside traditional batch pipelines, facilitating a smoother transition to a flexible, near-real-time ACH operating model. 

With redesigned ACH platforms, financial institutions and their corporate customers have the baseline to move across rails based on speed, cost, or business need. When banks have a modernized foundation, payment transactions can function with far less manual intervention. Financial institutions can then focus their attention where it is needed most: their customers. Banks that enhance their ACH architecture will define the next phase of the payments landscape, improving user satisfaction and closing the gap between expectations and execution.