# Billing Portal

The Billing Portal allows Merchant Customers to collect payment information from their Payer Customers using a hosted version of checkout.

The Billing Portal's primary use cases are situations where the environment from which a payment, payment method or scheduled payment needs to be collected, is not an active website.

Example use cases are payment or schedule buttons in an HTML email or PDF document.

## 📘  Billing Portal Base URL

The Base URL for loading the **Production** Billing Portal is [https://checkout.paystand.com/v4/](https://checkout.paystand.com/v4/)

### Sandbox Base Url

```http
https://checkout.paystand.co/v4/
```

with Parameters

```http
https://checkout.paystand.co/v4/?a.k=5csyxqnc417ao15u24p93fo0&paymentAmount=1.00&paymentCurrency=USD
```

Flattened Dot Notation Parameters

```text
https://checkout.paystand.co/v4/?a.k=5csyxqnc417ao15u24p93fo0&r.p.a=1.00&r.p.u=USD
```

## ❗️  Required Fields

Whether using dot notation or a single init parameter, each Billing Portal URL must specify at a minimum publishableKey (k) and currency (c). See [Checkout Attributes Reference](https://developers.paystand.com/reference/checkout-attributes) for details.