Event Handling

To receive events, you must set up a publicly accessible HTTPS endpoint and create a subscription that uses this endpoint. Our system will send HTTP POST requests to this endpoint with events encoded using JSON.

Your system must respond with a 2xx-series HTTP status code within 5 seconds of receiving a request to acknowledge successful delivery of a webhook notification. If this "success" response is not received by us within this time period, we will consider the delivery attempt as having failed and will later try to resend the message. We will attempt to redeliver messages at increasing intervals over a two week period. We will try at most 25 times to do this.

A recommended strategy for handling notifications is to do some basic validation and then store the notification for processing by a separate server process. This will avoid our delivery system from considering delivery attempts to have failed if your handler does not respond in time due to a long handling process. Basic validation could include signature verification (see below).

Event HTTP request bodies have a type-specific structure. Events using version 2 of our type schema will contain a common base structure with additional event-specific details. Each event type is described in detail later in this section.

Event HTTP requests also contain the following custom headers.

Signature header X-Signature-SHA256

Each outgoing webhook request is signed. You should verify that any request you handle was sent by Wise and has not been forged or tampered with. You should not process any requests with signatures that fail verification.

Signatures are generated using an RSA key and SHA256 digest of the message body. They are transmitted using the X-Signature-SHA256 request header and are Base64 encoded.

In this repository, you can see some reference implementations in Java, Node and Ruby.

Delivery ID header X-Delivery-Id

Each outgoing notification is assigned a unique delivery UUID.

Test notification header X-Test-Notification

This header is present with the value true if the notification is a test message.

Test messages can be sent to verify callback URLs when subscriptions are being set up.

Production Public Key
-----END PUBLIC KEY-----
Sandbox Public Key
-----END PUBLIC KEY-----

All event notification payloads have the same high-level structure. Top-level properties are common to all events. The data property is an object that can contain various properties. The exact properties that the data object contains depends on the event type and schema version of the event.

Common Properties

Event type- and schema version-specific details


ID of the webhook subscription that triggered the event notification


Event type (what event happened in our system)


Schema version (what notification structure is being used to model the event)


When the event notification was sent from our system

Basic Event Payload
"data": {},
"subscription_id": "01234567-89ab-cdef-0123-456789abcdef",
"event_type": "event#type",
"schema_version": "2.0.0",
"sent_at": "2020-01-01T12:34:56Z"