> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crossmint.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CrossmintCheckoutExistingOrder

> Flutter Final Class

**Final Class**

Reference an existing Crossmint order by ID.

```dart theme={null}
final class CrossmintCheckoutExistingOrder extends CrossmintCheckoutOrder
```

## Constructors

### CrossmintCheckoutExistingOrder

```dart theme={null}
const CrossmintCheckoutExistingOrder({
  required this.orderId,
  this.clientSecret,
})
```

## Properties

### orderId

```dart theme={null}
final String orderId
```

Identifier of an order previously created via the Crossmint orders API (server-side) or a prior embedded-checkout session. The hosted checkout resumes this order instead of creating a new one.

### clientSecret

```dart theme={null}
final String? clientSecret
```

Client secret returned alongside `orderId` when the order was created server-side. Required for orders created with a server API key so the hosted checkout can authorize against the existing order. Leave null when the current session already has access to `orderId` (for example, orders created from this same client).