Starting today, customers can create custom line items in AWS Billing Conductor (ABC) that span across multiple billing periods. For customers who want to apply consistent discounts or fees to specific billing groups, recurring custom line items remove the need to create a new custom line item each month for the same purpose. For example, customers can use a flat recurring custom line item to distribute credits or use percent-based recurring custom line items to apply a managed service fee or tax. ABC applies recurring custom line items at the beginning of each new billing period.
Source:: Amazon AWS