By default, the Billing API is not enabled. Therefore if you would like to use the API and benefit from enhanced invoicing automation, please activate the API via the url mentioned in the Introduction. On the “Your APIs” tab, after selecting ‘Settings’ you can generate an API key. Once generated you must enter at least on IP-address that will have access. You can generate multiple IP-addresses: for instance, one for development/test purposes and one for your production environment.
Once generated you must enter at least one IP address that will have access. In total, you can register
two IP addresses. For instance, one for development/test purposes and one for your production