> For the complete documentation index, see [llms.txt](https://docs.2checkout.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.2checkout.com/json-rpc-api-reference/json-rpc-api-6.0/api-requests/subscription-renewal/enable-recurring-billing.md).

# Enable recurring billing

Use the **enableRecurringBilling** method to switch on the automatic renewal system for a subscription that's manually renewable.

You can enable recurring billing for an addon subscription only while its main subscription is active and has automatic renewal enabled.

## Request parameters

<table><thead><tr><th width="215.066650390625">Parameter</th><th>Type / Description</th></tr></thead><tbody><tr><td><code>sessionID</code></td><td><p><strong>Required (string)</strong></p><p>Session identifier, the output of the <strong>Login</strong> method. Include <code>sessionID</code> into all your requests. 2Checkout throws an exception if the values are incorrect. The <code>sessionID</code> expires in <strong>10 minutes</strong>.</p></td></tr><tr><td><code>subscriptionReference</code></td><td><p><strong>Required (string)</strong></p><p>Unique, system-generated subscription identifier.</p></td></tr></tbody></table>

### Request sample

```php
<?php

require ('PATH_TO_AUTH');

$subscriptionReference = 'YOUR_SUBSCRIPTION_REFERENCE';

$jsonRpcRequest = array (
  'method' => 'enableRecurringBilling',
  'params' => array($sessionID, $subscriptionReference),
  'id' => $i++,
  'jsonrpc' => '2.0'
);

var_dump (callRPC((Object)$jsonRpcRequest, $host, true));
```

## Response parameters

<table><thead><tr><th width="107.3333740234375">Type</th><th>Description</th></tr></thead><tbody><tr><td><strong>Boolean</strong></td><td><strong>true</strong> or <strong>false</strong> depending on whether the changes were successful or not.</td></tr></tbody></table>

## Error codes

| Error codes                                 | Description                                                                                                    |
| ------------------------------------------- | -------------------------------------------------------------------------------------------------------------- |
| **ADDON\_AUTORENEWAL\_MAIN\_NOT\_ELIGIBLE** | Auto-renewal cannot be enabled for this add-on while its main subscription is not active with auto-renewal on. |


---

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