# Configure a custom Return Path

By default, Resend uses the `send` subdomain for the Return-Path address.

:::callout{intent="info"}
Domains that show `CNAME` records for sending use your Return-Path subdomain
for one record and an `r`-prefixed sibling for the other. With a Return-Path
of `outbound`, you'll be shown records for both `outbound.example.com` and
`routbound.example.com`, and both need to be added for the domain to fully
verify.
:::

You can provide a custom Return-Path address when you [add a new domain in the Dashboard](/guides/get-started-add-a-domain) under **Advanced options**, or by setting the optional `custom_return_path` parameter when [creating a domain via the API](/guides/domains-2-create-domain) or with [the `domains create` CLI command](/guides/resources-cli#domains).

:::callout{intent="note"}
The Return-Path is set when the domain is created and cannot be changed
afterwards, so `custom_return_path` is not accepted by the [Update
Domain](/guides/domains-2-update-domain) endpoint. To use a different
Return-Path subdomain, delete the domain and add it again with the new value.
:::

![Custom Return Path](../img/site-assets/mintcdn.com/resend/JHWt09hsc7E33HK2/images/dashboard-domains-resend-custom-return-path-g4wnig.png)

For the API, optionally pass the custom return path parameter.

:::code-group
```ts Node.js theme={"theme":{"light":"github-light","dark":"vesper"}}
import { Resend } from 'resend';

const resend = new Resend('re_xxxxxxxxx');

resend.domains.create({ name: 'example.com', customReturnPath: 'outbound' });
```

```php PHP theme={"theme":{"light":"github-light","dark":"vesper"}}
$resend = Resend::client('re_xxxxxxxxx');

$resend->domains->create([
  'name' => 'example.com',
  'custom_return_path' => 'outbound'
]);
```

```python Python theme={"theme":{"light":"github-light","dark":"vesper"}}
import resend

resend.api_key = "re_xxxxxxxxx"

params: resend.Domains.CreateParams = {
  "name": "example.com",
  "custom_return_path": "outbound"
}

resend.Domains.create(params)
```

```ruby Ruby theme={"theme":{"light":"github-light","dark":"vesper"}}
require "resend"

Resend.api_key = "re_xxxxxxxxx"

params = {
  name: "example.com",
  custom_return_path: "outbound"
}
domain = Resend::Domains.create(params)
puts domain
```

```go Go theme={"theme":{"light":"github-light","dark":"vesper"}}
package main

import "github.com/resend/resend-go/v4"

func main() {
	client := resend.NewClient("re_xxxxxxxxx")

	params := &resend.CreateDomainRequest{
		Name:             "example.com",
		CustomReturnPath: "outbound",
	}

	client.Domains.Create(params)
}
```

```rust Rust theme={"theme":{"light":"github-light","dark":"vesper"}}
use resend_rs::{types::CreateDomainOptions, Resend, Result};

#[tokio::main]
async fn main() -> Result<()> {
  let resend = Resend::new("re_xxxxxxxxx");

  let _domain = resend
    .domains
    .create(CreateDomainOptions::new("example.com").with_custom_return_path("outbound"))
    .await?;

  Ok(())
}
```

```java Java theme={"theme":{"light":"github-light","dark":"vesper"}}
import com.resend.*;
import com.resend.core.exception.ResendException;
import com.resend.services.domains.model.CreateDomainOptions;
import com.resend.services.domains.model.CreateDomainResponse;

public class Main {
    public static void main(String[] args) throws ResendException {
        Resend resend = new Resend("re_xxxxxxxxx");

        CreateDomainOptions params = CreateDomainOptions
                .builder()
                .name("example.com")
                .customReturnPath("outbound")
                .build();

        CreateDomainResponse domain = resend.domains().create(params);
    }
}
```

```csharp .NET theme={"theme":{"light":"github-light","dark":"vesper"}}
using Resend;

IResend resend = ResendClient.Create( "re_xxxxxxxxx" ); // Or from DI

var resp = await resend.DomainAddAsync( new DomainAddData {
   DomainName = "example.com",
   CustomReturnPath = "outbound"
} );
Console.WriteLine( "Domain Id={0}", resp.Content.Id );
```

```bash cURL theme={"theme":{"light":"github-light","dark":"vesper"}}
curl -X POST 'https://api.resend.com/domains' \
     -H 'Authorization: Bearer re_xxxxxxxxx' \
     -H 'Content-Type: application/json' \
     -d $'{
  "name": "example.com",
  "custom_return_path": "outbound"
}'
```
:::

Custom return paths must adhere to the following rules:

- Must be 63 characters or less.
- Must start with a letter, and end with a letter or number.
- Must contain only letters, numbers, and hyphens.

Avoid setting values that could undermine credibility (e.g. `testing`), as they may be exposed to recipients in some email clients.

## Related pages

- [Verified Domains](./learn-dashboard-domains-introduction.md)
- [Managing Domains](./learn-dashboard-domains-manage-domains.md)
- [Implementing DMARC](./learn-dashboard-domains-dmarc.md)
- [Implementing BIMI](./learn-dashboard-domains-bimi.md)
- [Open and Click Tracking](./learn-dashboard-domains-tracking.md)
- [Configure Transport Layer Security (TLS)](./learn-dashboard-domains-tls.md)
- [Choosing a Region](./learn-dashboard-domains-regions.md)
- [Claiming a domain](./learn-dashboard-domains-claim.md)

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