What is a private reply?

The message is addressed to a comment, not to a person. The app sending it names the comment’s ID as the recipient, which is how a business can reach someone who has never messaged it. Meta keeps the rules tight:

• One per comment. Each comment can be answered privately once, and only by the account it was left on.
• Seven days. The message has to go out within 7 days of the comment. Comments made during an Instagram Live can only get one while the broadcast is running.
• Text only. Meta’s documentation describes the private reply as a single text message. Buttons, cards and links have to wait for a later message.
• Followers and non-followers. The message lands in the main inbox of people who follow the account, and in message requests for everyone else.
• Volume. Instagram lets an account send at most 750 private replies an hour, which matters when a post suddenly takes off.
• Facebook too. A comment on a Facebook Page’s post can get one private reply, delivered in Messenger, under the same one-per-comment and 7-day rules.

Until the person answers, that one message is all the business can send. Their reply, even a single word, opens the normal messaging window, and the business then has 24 hours from it to send the link, a card with buttons or a choice of options. If they never answer, the conversation ends there.

So the first message works best as a question with an obvious answer. “Want the checklist? Reply YES and I’ll send it” gives people a reason to write back, and their YES is what lets the checklist through.

Tip: Non-followers find the private reply in their message requests, where it’s easy to miss. A public reply under the comment, such as “Sent you a DM. If you don’t follow us, check your requests”, points them to it.

The last column describes apps that send through Meta’s messaging API, auto-reply tools included. A typical comment-to-DM set-up pairs the first two: a short public reply so other people can see the account answers, and a private reply carrying the actual answer.

• Putting the link in the first message. Ask a question instead, and send the link once they answer.
• Answering spam. A private reply to a “check my profile” comment starts a chat with a bot. Skip comments that are only links or promotions.
• Messaging the same person again and again. Each comment allows its own private reply, so someone who comments five times could get five identical DMs. Answer each person once.
• Switching the automation on late. Comments more than 7 days old can no longer get a private reply, so set it up before the post goes live.