This plugin hasn’t been tested with the latest 3 major releases of WordPress. It may no longer be maintained or supported and may have compatibility issues when used with more recent versions of WordPress.

Lightweight Subscribe To Comments


This simply adds a subscription checkbox to your WordPress comments form to let your visitors subscribe to comments. They will then be notified by email when others comment on the same post. Works automatically upon activation, no settings required.

This plugin focuses on a lightweight footprint and fastest pagespeed. No scripts are added. It simply just works upon activation. All settings are optional.

Easily Switch From Other Comments Subscription Plugins

Your subscribers will be imported for an easy switch from the following listed plugins. This is done automatically upon activation. Your comment subscribers will be migrated from these plugins:

  • “Subscribe To Comments” plugin
  • “Subscribe To Comments Reloaded” plugin
  • “Comment Notifier” plugin

Optional Settings include:

  • You can unsubscribe people, if you wish.
  • You can customize the notification emails.
  • Set a custom “Unsubscribe Page” URL or unsubscribe message.
  • Send a “Thank You” message for first time commentators.
  • Send a copy of EACH notification to emails of your choice.

Special Condition For “Comment Notifier” Plugin Users:

“Lightweight Subscribe to Comments” fixes a major problem with the “Comment Notifier” plugin:

In particular, “Lightweight Subscribe to Comments” fixes this problem.

Lightweight Subscribe to Comments will not subscribe spammers while their comment is pending moderation. Only approved comments will be subscribed. Comments authors in moderation will only be subscribed if, and when, you approve their comment.

The problem is that “Comment Notifier” plugin subscribes the email address as soon as the submitted comment goes into moderation. This means that spammers get added to the list of subscribers, immediately. Later, when you delete the spam comments, the spammer’s email remains in the list of subscribers.

You could have hundreds, even thousands, of spammer email addresses in that list. Then, when you approve a legit comment, your server sends out emails to all of the post subscribers (including spammers), which can cause server overload, among other problems.

This plugin fixes that by ignoring comments in moderation until they are approved by you. This means less load on your server.

Bonus Clean Up For “Comment Notifier” Plugin Users:

This plugin removes spammers from your “Comment Notifier” list.

Upon activation, this plugin will clean up your “comment_notifier” list (database table) by removing all spammer emails (emails of people that do NOT have an approved comment). (This only applies to you if you were using the “Comment Notifier” plugin.) It will also empty your Comments “Trash” and “Spam”. This clean up is only done once, upon plugin activation.


This plugin is translation-ready and includes a .pot file to make it easy to translate.

See the Installation Guide.


  • This is the subscription checkbox that is added beneath your comment form.


Step 1: Install The Plugin

In your WordPress dashboard -> Plugins -> Add New, search for “Lightweight Subscribe To Comments”. Click “Install Now”, then click “Activate Plugin”.

Upon activation, the plugin automatically works. There will be a checkbox underneath your comment form so that visitors can subscribe to comments as they make a comment.

To troubleshoot a problem, see the Troubleshooting section on the full documentation page.

(Optional) Step 2: Maybe Add CSS Styles

Most themes do not need this step. If your theme uses common WP standards to load its stylesheet, your checkbox style will be just fine. However, if you notice that your checkbox is not aligned properly underneath your comment reply form, then see the documentation for a quick way to add the proper CSS style to align your checkbox.

(Optional) Step 3: Customize The Settings

If you want to customize any settings, then go to “Settings –> Lightweight Subscribe To Comments”. See the full documentation (link above).

(Optional) Step 4 – Only For Those That Were Using “Comment Notifier” Plugin

If you were using “Comment Notifier” plugin, then deactivate it right away to avoid having it add new spammers to your comment_notifier list. Only once, upon activation, this plugin will clean up your “comment_notifier” list (database table) by removing all spammer emails that were subscribed by the “Comment Notifier” plugin. It will also empty your Comments “Trash” and “Spam”. This is done automatically upon activation. Your existing approved comments, and legit subscribers, will remain intact.


Why are Test Emails not sending?

For test emails to work, you must enter an email address in the “Email address where to send test emails:” option, under “Advanced Settings”.
Tip: Do not use the sender address for this; some mail servers do not accept “from” and “to” set to the same value.

Where can I see more FAQ?

See all the FAQ.


November 24, 2021
I have tried many plugins for subscribing to new comments, and this one is the best for the settings inside, the possibilities for messages, performance and convenience! Many thanks to the developers! please support the plugin, I am ready to show one’s gratitude you!
March 4, 2021
Thank you for this plugin. Very easy to configure and completely functional. Well Done Isabel and again, thank you. From France.
October 3, 2020
This plugin is lightweight and very easy to use. However after using it for awhile I started to notice some items not working well. 1. The thank you email did not work at all but I did receive the test emails and I received an email when I did a test reply. I noticed in the forum there has not been a response for about 10 months so not sure if this plugin offers support. For us we had to uninstall this plugin because it did not fully work. However I gave it 4 stars for the lightweight and simplicity. But with all the laws of GDPR and privacy policy etc. I think a more complex plugin would be appropriate for us.
October 2, 2020 1 reply
Easy and useful! Nice Plugin, although it may have problems with GDPR? I still miss some features. But most I miss, that the author hasn’t answered for questions since more than a year. Well, it’s a free plugin, so I don’t wanna whine – but: what a pity. Thanks anyway!
August 15, 2020
Simple is beautiful! I just started today to use this plugin and I am loving it!
Read all 25 reviews

Contributors & Developers

“Lightweight Subscribe To Comments” is open source software. The following people have contributed to this plugin.


“Lightweight Subscribe To Comments” has been translated into 3 locales. Thank you to the translators for their contributions.

Translate “Lightweight Subscribe To Comments” into your language.

Interested in development?

Browse the code, check out the SVN repository, or subscribe to the development log by RSS.



  • Fix – Deleting comments from the Trash caused PHP errors.
  • Build – Removed deprecated functions and options.


  • New – Added new Theme Compatibility option to “Show Checkbox After The Comment Form.” If the checkbox is not appearing on your comment form, enable this option. Enabling this option will make the checkbox work on a larger variety of independent themes (themes that do not use standard WordPress comment form filters). This will add the checkbox below the comment form submit button.
  • Fix – Added compatibility for languages with non-Latin characters such as Cyrillic, Arabic, and Hebrew. Previously, names with non-Latin characters were displayed incorrectly in the notification emails. Note that this update fixes this issue, but it may be an hour or more, after you update, before the fix first takes effect. If you have a large database with thousands of posts it may take as much as several hours before the fix is complete.


  • New – Added option to delete all plugin data on uninstall. Enabling this option will delete the subscriber list and their subscriptions when the plugin is deleted.
  • Tweak – Added compatibility with more themes. Use comment_form_after_fields hook instead of comment_form_submit_field hook to show the checkbox.


  • Fix – If comment moderation was NOT enabled, subscribers were not properly subscribed in version 1.5.4. The problem was due to trying out the new $commentdata argument, which was added in WP 4.5. This issue has been fixed by reverting the use of the $commentdata arg.
  • Fix – Removed 2nd argument from comment_form_submit_field filter.


  • New – Moved the subscription checkbox above the submit button.
  • API – Use the $commentdata arg, which was added in WP 4.5, on comment_post hook.
  • API – Use $wpdb->prefix instead of constructing the prefix from base_prefix.


  • New – New option to disable the inline CSS styles.
  • Fix – Don’t import invalid subscribers from other plugins. Version 1.5.2 had a bug which would import subscribers from “Subscribe to Comments Reloaded” and “Subscribe to Comments” plugins, as is. Now, only subscribers with valid emails will be imported from those plugins. (This bug did not apply to you if you had never used either of those 2 plugins.) In addition, upon updating to version 1.5.3, any invalid spammy subscribers that were erroneously imported from other plugins will be removed from our subscriber list. However, note that we do NOT remove any data that was inserted and attached to the posts by those 2 plugins. This means that if you had spammy, invalid subscribers with invalid emails attached to your posts, they still remain there because this plugin doesn’t modify any postmeta. Those 2 plugins attach the subscribers to the actual post as “postmeta” and that data will remain there unless those plugins have a way to remove its data. (I will soon release an extra utility plugin that you can use to clean that data from those plugins.)
  • Tweak – Add scrollbars to the message preview in the settings page.
  • Tweak – Simplify settings names.


  • New – Easily switch from the “Subscribe to Comments” plugin by Jaquith. Also, improved importing for subscribers from the “Subscribe to Comments Reloaded” plugin.
  • New – Replace tags with sample text in preview. This means you get a better preview of the message body when you click “preview”.
  • Fix – Fixed a bug that would delete the plugin settings (not subscribers, just settings) upon plugin deactivation. This is fixed, and currently, settings are kept intact. Future updates will bring an option to erase all data.
  • Tweak – Added the {comment_link} to the list of tags available for editing the message body.


  • New – Updated the .pot translation file.
  • Fix – Options were not migrated in version 1.5. This properly migrates the options to the new handle. If you are on version 1.5, and you don’t update to 1.5.1, then you would have to go into the settings page and click “Save” to save the new options. Or simply update to version 1.5.1 which takes care of that.


  • New – Simplified settings page. All settings are optional. The plugin now works upon activation without the need to configure any settings. HTML p tags have been removed from the message textareas to make it easier to customize the messages. There is now only 1 Save button on the settings page, rather than 3.
  • New – Changed plugin name to Lightweight Subscribe To Comments.
  • New – Upon activation, will migrate subscribers from the “Subscribe to Comments Reloaded” plugin for an easy switch from that plugin to this one.
  • Fix – Update values on the settings page after saving and sending test email. Previously, the email to send test emails to was not refreshing on the page even though it was being saved.
  • Tweak – textdomain in now loaded on init which helps ensure that translations work.


  • Fix – Removed annoying admin notice. It will only show up once upon plugin activation, only if spam/pending commenter emails were removed from the database.
  • Fix – Fixed incorrect textdomain. The correct textdomain is comment-notifier-no-spammers.


  • Fix – If using paged comments, the comments link may have been wrong if it was a comment that appeared on a page other than the first comments page.
  • Tweak – Change h2 heading tag on Settings page to h1.


  • New – Removed inline CSS for subscription checkbox. Added new CSS selectors for easier styling: p.cnns-comment-subscription and label#cnns-label.


  • New – If you were manually adding the subscription checkbox to your template files, you must update it since the input checkbox code has changed. Specifically, the name and id of the checkbox input has changed from ‘subscribe’ to ‘cnns_subscribe’. See the settings page for the whole snippet.
  • Fix – Every approved comment author was being subscribed, whether they checked the box to subscribe, or not.
  • Tweak – Improved some option descriptions.
  • Maintenance – Removed a PHP notice.
  • Maintenance – Updated .pot translation file.


  • Fix – Removed several PHP errors from the options page.


  • Fix – Removed fatal error which occurred when trying to delete a subscription from the admin.
  • Maintenance – Removed a couple of PHP notices.
  • Maintenance – updated .pot translation file.


  • Added plugin URI.


  • First release.