Title: comment_notification_subject
Published: April 25, 2014
Last modified: February 24, 2026

---

# apply_filters( ‘comment_notification_subject’, string $subject, string $comment_id )

## In this article

 * [Parameters](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#parameters)
 * [Source](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#source)
 * [Related](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#related)
 * [Changelog](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#changelog)

[ Back to top](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#wp--skip-link--target)

Filters the comment notification email subject.

## 󠀁[Parameters](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#parameters)󠁿

 `$subject`string

The comment notification email subject.

`$comment_id`string

Comment ID as a numeric string.

## 󠀁[Source](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#source)󠁿

    ```php
    $subject = apply_filters( 'comment_notification_subject', $subject, $comment->comment_ID );
    ```

[View all references](https://developer.wordpress.org/reference/files/wp-includes/pluggable.php/)
[View on Trac](https://core.trac.wordpress.org/browser/tags/6.9.4/src/wp-includes/pluggable.php#L1974)
[View on GitHub](https://github.com/WordPress/wordpress-develop/blob/6.9.4/src/wp-includes/pluggable.php#L1974-L1974)

## 󠀁[Related](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#related)󠁿

| Used by | Description | 
| [wp_notify_postauthor()](https://developer.wordpress.org/reference/functions/wp_notify_postauthor/)`wp-includes/pluggable.php` |

Notifies an author (and/or others) of a comment/trackback/pingback on a post.

  |

## 󠀁[Changelog](https://developer.wordpress.org/reference/hooks/comment_notification_subject/?output_format=md#changelog)󠁿

| Version | Description | 
| [1.5.2](https://developer.wordpress.org/reference/since/1.5.2/) | Introduced. |

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