What is Faster Payments (FPS)?
A short primer on the UK Faster Payments Scheme — what it is, who runs it, how a payment flows, and where error codes come from.
The scheme in a sentence
The Faster Payments Scheme (FPS) is the UK system for near-instant, low-value sterling payments between bank accounts, available around the clock. It is what sits behind most everyday transfers — single immediate payments, standing orders, and many app-based "send money" flows.
Who runs it
Faster Payments is operated by Pay.UK, the operator of the UK's retail interbank payment systems. Banks, building societies, and fintechs (collectively payment service providers, or PSPs) connect to the scheme either directly or through a directly-connected sponsor under an agency arrangement.
The payment lifecycle
A payment is created by the sending PSP, passed through the scheme, and presented to the receiving PSP, which decides whether it can credit the destination account. If everything checks out the funds settle between the banks and the payment is complete. Problems can surface at two distinct points, and that distinction is exactly what the error codes capture.
Reject (pre-acceptance)
A reject happens before the payment is accepted. The receiving bank or the scheme refuses the message up front, so no money moves. These are the numeric REJ codes.
Return (post-acceptance)
A return happens after a payment has been accepted and settled — the receiving bank later sends the funds back, often because the account cannot keep the credit. These are the RET codes.
Who issues these codes
Reject and return codes are produced by the receiving PSP or the scheme as part of normal message processing, and relayed back to the sending PSP so it can act and inform its customer. The official FPS technical specification that defines them is restricted to scheme participants, so this site aggregates codes from publicly available bank and technology-partner documentation — see the references.
Where this is heading: ISO 20022 and the NPA
The UK is modernising its retail interbank payments through the New Payments Architecture (NPA), led by Pay.UK, which adopts the global ISO 20022 messaging standard and its set of external return reason codes. Over time the current numeric FPS codes will map onto ISO 20022 codes; exact codes and timelines vary and are still evolving. You can explore the FPS to ISO 20022 mapping and the future codes reference.
Next steps
Browse every code on the codes page, or read the FAQ for quick answers on rejects, returns, and retrying payments.