{"section":"tutorials","requestedLocale":"en","requestedSlug":"inserting-taxes-in-the-cart","locale":"en","slug":"inserting-taxes-in-the-cart","path":"docs/en/tutorials/checkout/checkout-settings/inserting-taxes-in-the-cart.md","branch":"main","content":"For some stores, especially those that operate in a B2B model, tax calculations can be so complex that it is necessary to use an external tax calculation provider. For such cases, it is possible to build an integration to connect stores to these services.\n\n## How it works\n\nWhenever an item is added to the cart on your VTEX store, the platform triggers a series of automatic processes in order to ensure fulfillment. \n\nSynchronous integration allows these automatic processes to send product data to the external tax calculation tool whenever a change is made to the cart. The tool must then respond with appropriate information on the calculated taxes.\n\n## Implementing integrations with tax calculation services\n\nAccess our [Tax service integration guide](https://developers.vtex.com/vtex-developer-docs/docs/tax-service-integration-guide) to know more about how it works and how to implement it."}