Circle’s webhooks are an automated method for apps to receive notifications the
moment a transaction is completed or fails to complete. Circle will make a
request to your application when an operation is completed. That means your app
doesn’t need to poll Circle to know whether an operation has completed in the
blockchain—the confirmation will arrive automatically.
For configuring a notification subscriber endpoint, see the
Notifications Quickstart.
Set Up Subscriptions
Through the Circle UI in Sandbox or Production, you can set up webhook
subscriptions. This can be done by:
- Navigating to Developer → Subscriptions in Sandbox or Production.
- Selecting Add Subscription
- Entering an endpoint URL you would like notifications to go to.
- Selecting Add Endpoint
Automatic subscription removal All subscriptions in sandbox are removed after 30 days.
View Subscriptions
Via Circle’s UI you can view all subscriptions registered to your account on
Developer → Subscriptions. Circle’s Sandbox environment permits up to three
subscriptions and the Production environment supports one.
Remove Subscriptions
While viewing subscriptions you are also provided the option to remove
subscriptions. This is done by simply selecting kebab on the Endpoint and
selecting remove.
API Endpoints
All these actions can also be done using Circle’s APIs. See
API reference subscriptions
for more detail. 
