The step that writes a public reply under the comment that started the flow: the text pool, the 2,200-character limit, the per-run writing allowance and the cases where the step is skipped.
Sending a private message to someone who commented on your post is only half the job; the other half is a visible answer underneath the comment itself. Comments left hanging make you look absent, and they tell everyone else scrolling past that nobody answers here. The Comment reply step writes a public reply under the comment that started the flow. This guide covers its settings, its limits, and every case in which it is skipped.
⚠️ Note: This step works on Instagram only, and it is only useful when the flow started from a comment (a post comment or a mention). On a WhatsApp account it never appears in the step list.
What it does
The step writes a reply in your name underneath the comment that opened the run. This is not a message: it does not go to the person privately, everyone can see it, and the 24-hour messaging window does not apply to it.
The usual purpose is to send the commenter to your inbox: the private reply lands in their DMs while the comment thread shows "Sent you a DM, check your inbox 💌". Both the commenter and everyone reading the post see that they got an answer.
This reply used to be a setting inside the comment trigger; it is now its own step, so you can place it anywhere in the flow — after a condition, for example.
Settings
Reply texts
This is the step's only setting. Add a reply with Add text and remove one with Remove text. You can write up to 5 texts, and one of them is picked at random for every comment.
Writing more than one matters. Thirty identical sentences under the same post make the account look careless and automated. Three or four wordings are enough:
Sent you a DM, check your inbox 💌
Details are in your messages 🙌
Just messaged you — take a look ✨
Placeholders work in these texts. Remember though: this reply is public. Do not put anything personal beyond {{contact.first_name}} here — no email addresses, no phone numbers, no custom fields.
Its output
The step has one output, Next. Whether the reply was written or not, the flow continues from there; the step never stops a run.
The common arrangement is Start (post comment) → Comment reply → Message (the private reply). The order can be reversed; neither waits for the other.
When the step is skipped
The Comment reply step does not throw errors. When the conditions do not hold it is skipped quietly and the reason is written to the run log.
No comment context. The flow started from a keyword or an ad, so there is no comment to write under.
The channel is WhatsApp. If the conversation is running on WhatsApp, the step is skipped.
The text pool is empty. If no text was written, the pre-publish check already reports an error.
The per-run writing allowance is used up. A single run writes under the comment at most 3 times. This stops a looping flow from filling a comment thread.
The comment was deleted. If the person removed their comment there is nothing to reply to, and the log says the comment was not found.
An example
A florist wants to handle the "price?" comments coming in on a Valentine's Day post.
They add a Post comment trigger to the Start step, pick that post in the post picker, and set the keyword to price.
They add a Comment reply step with three texts: "Prices are in your DMs 💐", "Check your messages 🌷", "Details are in your inbox ✨".
They connect a Message step after it: "Hi {{contact.first_name|there}}, here are our bouquet prices…" — plain text, because the first message out of a comment cannot carry buttons.
After the message they add an Action step that applies the valentines tag.
The result: everyone who comments sees an answer under the post and gets the price list privately, and the florist can follow up on who asked using the tag.
Common mistakes
Putting the step in a flow with no comment trigger. It is skipped on every run. The panel shows this both under the step and in the pre-publish check.
Writing one text and leaving it. It works, but the comment thread fills up with the same sentence. Add at least three wordings.
Treating the reply as private. Everyone sees what you write here. Prices, addresses and coupon codes belong in the private message.
Going over 2,200 characters. Instagram accepts at most 2,200 characters in a comment — the same measure as a post caption. Text beyond that blocks publishing, and a reply that does get through is trimmed. Do not confuse this with the DM limits; they are separate.
Building a loop to write on every turn. There are three writes per run; the fourth is skipped.
Using it on a flow whose account also has WhatsApp. With both channels connected the step appears in the list, but it does not run in WhatsApp conversations, and the check warns you about it.
Limits
Up to 5 reply texts, each at most 2,200 characters (the limit is on Instagram's side).
At most 3 replies per run.
Instagram only, and only in flows that start from a comment or a mention.
The step depends on your plan: when it is out of scope the list shows Not in your plan and the run stops here.
Writing a reply does not open the 24-hour window; you still cannot send free-form messages until the person writes to you.
Related concepts
For the rules that govern the private message going to the commenter, see The Message step. Hiding or deleting a comment is handled in The Action step. If replies are not being written, the Comment replies are not going out guide walks through the causes in order.
One sentence under a comment tells everyone who sees the post that somebody is home.