Payment processing phases

Payments are processed through a series of validation and execution phases before funds are delivered to the recipient.

The exact flow depends on how the payment is initiated:

• Payment request → transaction
• Transaction only

In all cases, the transaction is the execution phase where funds are transferred.

Overview

Payment processing combines:

• Payment lifecycle – tracks the status of a payment request and transaction
• Transaction processing phases – describe how a transaction is validated and executed

See Payment lifecycle.

Processing model

A payment follows this high-level flow:

1. Payment request (optional)
2. Transaction creation
3. Synchronous validation
4. Asynchronous processing
5. Settlement and notification

Synchronous processing

The first stages occur when the request is received.

Verification

The system verifies that the request is valid and authorised.

This includes:

• Validating authentication credentials
• Confirming the request structure
• Validating basic fields such as currency and country codes
• Confirming access to the funding account

Validation

The system validates the transaction against country and payment method rules.

This includes:

• Checking required banking fields
• Validating field formats and lengths
• Ensuring the payment can be routed

If validation succeeds, the transaction is accepted for processing.

Asynchronous processing

After validation, the transaction enters the processing pipeline.

Duplicate checking

The system checks for duplicate requests to prevent the same payment from being processed more than once.

Transaction processing

The system prepares and submits the transaction for execution.

This includes:

• Queueing the transaction
• Grouping transactions into batches
• Submitting transactions to banking partners or payment networks

Balance validation

The system performs a final balance check before execution.

A transaction may fail at this stage if sufficient funds are no longer available.

Settlement

The payment is executed and funds are transferred to the recipient.

Settlement timing depends on:

• Payment route
• Cut-off times
• Processing conditions

See Country and currency coverage.

Notification

The system records the outcome and notifies your integration.

Notifications are typically delivered via webhooks when a transaction reaches a terminal state.

See Webhooks.

Relationship to lifecycle

Processing phases describe how a transaction is executed.

Lifecycle topics describe how its status changes over time.

Use both together to:

• Understand how payments are processed
• Track progress and outcomes
• Diagnose delays or failures