FedNow and RTP now carry a meaningful share of US account-to-account volume, and Canada’s Real-Time Rail is on its way. The appeal is obvious. The money arrives, the payer knows, the payee knows, and the transaction is done. What gets less attention is what “done” means for a fraud team. There is no next morning to review the queue. There is no recall. If a scam payment or a mule-account transfer clears, the loss is booked at the moment of settlement.

Most fraud tooling in mid-sized banks and credit unions was designed for a different clock. Card fraud gave institutions an authorization window and a chargeback process behind it. ACH gave them a batch cycle. Real-time rails give them somewhere under a second, and in practice a good deal less, because the rail itself consumes part of that budget.

That is why the two losses everyone is discussing this week, authorised push payment scams and mule accounts, are so hard on instant rails. In an APP scam the customer is the one pressing send. The credentials are valid, the device is theirs, the amount may sit well inside their normal range. What gives the scam away is context: a new beneficiary, a pattern that looks like coaching, a destination account whose own behaviour looks like a mule. None of that is visible to a rules engine that sees the transaction on its own, and none of it helps if the score arrives after the money has gone.

Nacha’s Phase 2 fraud-monitoring rules, in force since 19 June 2026, now require risk-based monitoring across ACH with no volume threshold. Instant rails have nothing equivalent yet. The institution’s own controls are the only line.

Our view is that real-time scoring has to be treated as base infrastructure for a real-time rail, in the same way authorization is base infrastructure for cards. We built the fraud and risk layer that scores India’s UPI, the largest real-time rail in the world, and we run it at national scale: more than 20 billion transactions a month across 1,500+ institutions, returning a decision in under 100 milliseconds at 99.999% availability. We also co-architected Canada’s RTR Exchange. That experience taught us three things that matter more than any single model.

The first is that the check has to sit in the payment path, between the customer’s instruction and the rail. Anything bolted on afterwards is reporting, not defence.

The second is that speed and accuracy stop being a trade-off once the scoring layer already knows the customer. Behavioural context, device, beneficiary history and the incumbent fraud score can all be combined inside the latency budget, provided the profile is built continuously rather than assembled on demand.

The third is that the institution must keep the decision. The scoring layer produces the risk, the reason and the record. Step-up, hold or release stays with the bank. That matters for liability as much as it matters for trust.

If your existing fraud platform was built for cards or for batch, you do not have to replace it to get there. It becomes one of the inputs. What changes is where the decision is made, and how quickly.

About RS Software
As the payments ecosystem transitions toward an AI-driven, real-time, and increasingly autonomous model, where TRUST is the new currency, RS Software (India) Limited's product portfolio modernizes the most critical areas across the value chain, leveraging decades of work building mission-critical payment infrastructure globally. Each product is purpose-built to address specific structural shifts in the market while collectively enabling a unified, AI-led financial ecosystem. RS IntelliEdge™ is designed to address evolving transaction-level controls and shift to continuous, identity-centric intelligence systems, protecting approximately 95% of India’s digital payment transactions and screening billions of transactions each month. RS DigitalEdge™ is designed to enable real-time routing, optimization, and decisioning across payment flows. Payabbhi® is designed to enhance the acceptance and acquiring layer, transforming it into a data-driven revenue engine. www.rssoftware.com