The Invoice API will respond with following HTTP status codes if an error occurs while processing your request. We expect the client code to catch these errors with a fallback mechanism.

Error Information
Parameter Description

Access Denied – User is not authenticated. Please check whether you passed the correct api_token with your request.


Permission is denied. This might happen if you try to access resources that the user does not have permission to access.


Bad Request – The request is not correctly formatted or is missing some parameters. Verify whether you have properly constructed the XML or JSON request and have included all the required parameters.


Not Found – The endpoint you trying to access does not exist.


Server Error – Something is wrong with the server. Try again in a couple of minutes and if it's a recurring error, please contact InvoiceApp Support.

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Content type for responses will always be application/json.

Use HTTPS only! Any HTTP requests will be ignored.

On a successful request of access token, remember to put the authorization token in all your request headers!.

The Invoice API uses the 200 response code for all successful request.

All usage of the Invoice website API, and services is subject to the company's terms and conditions and all annexed legal documents and agreements.

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