Chargebee's Account hierarchy feature allows you to map the organizational structure of your customers by the line of business or geography. Currently, there is a limit of 25 child accounts per parent account.
To extend this value per customer contact support.
Note: It is recommended to maintain child accounts <250 as the limit is imposed based on the number of line items expected on a single child subscription.
For example, If a parent account is entitled to receive a consolidated invoice of 300 child accounts, with ~3 line items each (including plan, addon, and coupon)then, Chargebee will not be able to process the invoices as they might contain more than 800-900 line items.
Related articles and Documentation
How does parent billing work when invoices are consolidated?