Cost
App Service Builder usage is offered at no charge during the initial preview period, subject to preview access conditions and service limits. Use it for development and test only; do not deploy production workloads.
This describes the initial preview offering, not a permanent free tier or a fixed-duration free entitlement. Confirm access conditions and limits with your preview contact before deploying.
Limits during preview
Service limits protect shared preview capacity and help prevent abuse. Quotas and limits lists configuration limits and default preview policies. Your subscription's effective allowances can differ. Confirm app, build, scaling, and traffic allowances with your preview contact; no-charge usage is not unlimited usage.
Separately billed services
Azure resources and services you provision separately can have their own charges. For example, storage, databases, model inference, and external APIs are not made free by the Builder preview offer. Confirm those services' pricing and remove resources you no longer need. The Portal and CLI quickstarts include deleting your Builder app; separately created resources require their own cleanup.
Private Preview guidance explains the development/test restriction and links the Azure Preview terms. Regions explains the availability information required from preview onboarding.