# Changing the subscription's external reference identifier

Keeping your subscription data synchronized across various platforms and systems is imperative for operational efficiency and accuracy. Occasionally, you may need to update a subscription's [external reference identifier (ERID)](https://docs.digitalriver.com/commerce-api-references/commerce-api-reference-guide/api-structure/product-external-reference-identifier-erid) to ensure this synchronization. This guide walks through updating an existing subscription's external reference identifier. Such updates help maintain the integrity of your data across systems and enable a more streamlined management of subscriber information. Whether you're integrating new systems or need to adjust for accurate tracking, this guide will assist you in making the necessary changes with ease.

send a [`POST /v1/subscriptions/{subscriptionId}/reference-id`](https://docs.digitalriver.com/commerce-api-references/admin-apis/subscription-mangement/modify-the-subscriptions-external-reference-id#v1-subscriptions-subid-reference-id) request to change the subscription's external reference identifier. Replace `{subscriptionId}` with the actual ID of the subscription you're looking to update. Make sure to replace `{YOUR_AUTH_CREDENTIALS}` with your actual encoded API credentials. Replace `{NEW_EXTERNAL_REFERENCE_ID}` with the new identifier you want to assign.

{% tabs %}
{% tab title="cURL" %}

```javascript
curl --location --request POST 'https://api.digitalriver.com/v1/subscriptions/{subscriptionId}/reference-id' \
--header 'Authorization: Basic {YOUR_AUTH_CREDENTIALS}' \
--header 'Content-Type: application/json' \
--data-raw '{
  "externalReferenceId": "{NEW_EXTERNAL_REFERENCE_ID}"
}'
```

{% endtab %}
{% endtabs %}

Upon successfully making the request, you will receive a `202 Accepted` response indicating that updating the external reference identifier is underway. The new plan will go into effect immediately.


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