Glossary
Private reply
A private reply is a direct message an Instagram professional account sends to someone in response to their comment, addressed by the comment's ID instead of a user ID. Meta allows one private reply per comment, sent within 7 days of the comment, or during the broadcast for Instagram Live. Meta's documentation notes that the message includes a link to the post that was commented on.
The rules in Meta's documentation
Only one message can be sent to the commenter. It has to go out within 7 days of the comment. For Live, private replies only work while the broadcast is running and stop when it ends. Follow-up messages are only allowed if the person responds, and then within 24 hours of their response. Meta lists comments on posts, reels, stories, Lives and ads as sources a private reply can answer.
Where the reply lands
According to Meta, the reply appears in the person's inbox if they follow the professional account, and in their message requests folder if they do not. That is why many creators add a line like "check your requests" to the caption.
How it is sent
The app sends a POST request to the account's /messages endpoint with recipient set to { comment_id }. With the Instagram API with Instagram Login this needs the instagram_business_basic and instagram_business_manage_comments permissions, plus the comments or live_comments webhook field to hear about new comments. The response returns the commenter's Instagram-scoped ID and the message ID.
Meta's rate limit for private replies is 750 calls per hour per account for comments on posts and reels, and 100 calls per second for Live comments.
For how this fits into the whole flow from comment to DM, read How comment-to-DM automation works.
Sources
- Meta for Developers: Send a Private Reply to a Commenter
- Meta for Developers: Instagram Platform overview: rate limiting
Checked against Meta's documentation on 2026-10-20. Meta changes its rules from time to time, so its pages are the final word.
