In Chargebee, when consolidated invoicing is enabled, the subscription renewals and unbilled charges for a customer are consolidated into a single invoice. Any 1st invoice raised when a new subscription is created/activated (including those activating after a trial period and those set to start at a future date) is always invoiced separately unless added to unbilled charges.
To avoid a separate 1st invoice, create a new subscription having the Invoicing options set to “Add to Unbilled charges” You can do this via the UI or API.
Using UI: Go to, Chargebee Dashboard > Subscriptions > Create Subscription > Invoicing options
Info: You will not be able to consolidate your invoices if charges for the customers are not due to be invoiced on the same day if charges from the subscriptions have different auto-collection status etc. To know more on why your invoices are not getting consolidated, refer to this article.
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