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Testing process

You must test the compatibility of your software with CTC Guarantee Balance API v2.0.

The API lets you submit guarantee balance request notifications into our sandbox testing environment.

You can test your software by using our sandbox to ensure that its connectivity works properly with HMRC systems.

Trader Test uses the same NCTS and Guarantee Management System (GMS) code as live production but populated solely with test data. This allows you to test the full journey using your software.

You must:

  • test common scenarios based on the test data that we have provided
  • check your test results against our JSON schemas to ensure that your API requests are valid