Test payments in sandbox
Resources for payments testing including collections, sandbox environment and mock providers.
See our GitHub for libraries and SDKs to help you integrate the Payments API v3.
Collections
Our collections are sets of preconfigured requests that help you to test API requests as quickly as possible. For Payments, we use the Insomnia REST API client.
If you have Insomnia installed, download and install the TrueLayer collection.
The TrueLayer Insomnia plugin simplifies the process of signing your requests.
Sandbox
To enable the sandbox environment in Console, ensure that the Live toggle in the top-right corner is toggled off (it will be greyed out).
While live is toggled off, any changes you make in Console apply to sandbox, but not the live environment.
To test your API requests in the sandbox or live environments, use these base URLs:
Sandbox | Live |
---|---|
https://api.truelayer-sandbox.com/ | https://api.truelayer.com/ |
To learn how to create test payments in our sandbox environment, see our quick start guide.
Mock providers
TrueLayer provides mock providers for each country with payments API v3 . You can use these to test your integration, regardless of whether you integrate with our web UI, mobile app UI or a direct API integration.
Based on how you create the payment, you see different banks available within the HPP or SDKs as you test. For a direct integration, you would observe this take effect in the list of providers you receive for provider_selection
action.
Redirect Flow
To make the relevant providers visible during authorisation ensure that:
provider_selection.type
is set touser_selected
provider_selection.filter.countries
is either empty or filled with the ISO-3166-1 alpha-2 country code (e.g.GB
,IE
,DE
)currency
is set accordingly to the country code
When you initiate a payment using one of these providers, we return a URI that redirects your user to our mock provider authorisation page.

The UI for the mock provider.
On the authorisation prompt page, different actions lead to different outcomes for the payment:
Outcome | Action |
---|---|
Execution | Enter username test_executed |
Auth failure | Enter username test_authorisation_failed |
Execution rejection | Enter username test_execution_rejected |
Cancellation | Click cancel button |
Using test_executed
or test_execution_rejected
enables the Execution delay selection, where you can select from different timings, from no delay to one day.
Using test_executed
enables the Settlement delay selection, where you can select from different timings, from no delay up to one day.
When you log in with one of the previous usernames, the mock provider presents the account selection page.
When you provide the remitter account details in the payment initiation request, only the stated account can be selected on this screen.
Sandbox payment limit
You cannot make a payment with an amount_in_minor exceeding
5000000
to a merchant account in the sandbox environment..
Updated 3 months ago