> ## Documentation Index > Fetch the complete documentation index at: https://docs.voiceaiwrapper.app/llms.txt > Use this file to discover all available pages before exploring further. # External Billing Overview > How External Billing works and who it is for. ## What is External Billing? External Billing is the module that lets your agency charge clients directly for their usage of Voice AI Wrapper - outside of any platform-level subscription you may have. You define your own plans, set your own prices, and collect payment however you prefer. The platform tracks minutes, enforces access rules, and keeps a full payment history; you handle the actual collection. External Billing is separate from the internal Stripe billing that covers your agency's own platform subscription. It is entirely about what you charge **your clients**. ## How agencies use it The overall workflow has three phases: 1. **Set up your catalog** - Create one or more billing plans and, optionally, add-on packs in External Billing configuration. Plans define the price, billing rhythm, included minutes, and whether overage or add-on packs are allowed. 2. **Assign a plan to a client** - On the client's **Billing** tab, pick a plan from your catalog and assign it. Once a plan is assigned, the client can see it in their portal and you can start a subscription on their behalf. 3. **Manage the subscription and payments** - Once a subscription is active, the platform automatically generates payment requests on each billing cycle and tracks usage. You manually mark payment requests as paid (or failed/canceled) after you collect payment through your preferred channel. ## Key concepts | Term | What it means in the UI | | ------------------- | --------------------------------------------------------------------------------------------------------------------------- | | **Plan** | A billing product you create: price, interval, included minutes, overage rate, and add-on pack eligibility. | | **Subscription** | An active billing relationship between your agency and one client, based on a plan. Tracks the current period and status. | | **Payment request** | A single invoice line for a billing cycle (type **Cycle**) or an add-on pack purchase (type **Pack**). | | **Add-on pack** | A one-time block of minutes a client can purchase on top of their plan's included minutes. | | **Wallet** | The accumulated add-on minutes balance for a client. Wallet minutes never expire and do not reset at period end. | | **Billing period** | The date range for the current subscription cycle. Included minutes reset when each period ends. | | **Client portal** | The Billing page your clients see when they log in: current plan, usage, available add-on packs, and their payment history. | ## How the pieces connect Subscription Billing Flow: agency creates a plan, assigns it to the client, starts subscription, platform tracks usage; when the period ends, a new cycle payment request is created, the agency marks it paid, and the next period begins. Add-on path: from start subscription, agency applies add-on pack, pack payment request created, then agency marks as paid. ## What the client sees Clients log in to their portal and see: * Their **Current Plan** name, pricing, and billing period. * **Usage This Period** - how many included minutes they have used, any add-on balance, and any billable excess. * **Available Add-On Packs** - packs you have assigned to them, with a note to contact you to purchase. * **Payment requests** - a full table of all charges, their status, and due dates. If a payment is overdue or the subscription is blocked, prominent banners appear and all running campaigns are paused automatically.