Yes. A comment on a Reel sends a DM exactly the way a comment on a normal post does, because Instagram treats the two the same. Two things have to be true: the comment has to be left directly under the Reel rather than as a reply to somebody else's comment, and it cannot be your own.
Do Reel comments work the same way post comments do?
Yes, and there is a simple reason. Instagram does not treat a Reel as a different kind of thing. Your posts, Reels and carousels all come through together, and when somebody comments, Instagram tells us straight away which piece of content they commented on. So a tool that can turn a comment on a normal post into a DM does the same on a Reel, with nothing extra to switch on.
What changes between a post and a Reel is who is in the comments, not how it works. Reels are what Instagram shows to people who do not follow you yet, so the comments fill up with strangers instead of your regulars. That is why this matters more on a Reel: turning those comments into DM subscribers is the whole point, and a Reel is where the new names arrive.
What will not trigger anything?
Four things, and the first two are the ones that catch people out.
A reply to somebody else's comment. Automations only answer comments left under the Reel itself. This trips people up more on Reels than anywhere else, because Reel comments turn into conversations fast: somebody types your keyword as a reply inside a thread, and nothing happens. If your automation is not sending, rule this out first.
Your own comment. Your own comments are ignored on purpose, so you cannot test your automation by commenting the keyword on your own Reel. It will look broken when it is working perfectly. Use a second account, or ask a friend.
The caption. The keyword has to be typed by a viewer, in the comments. Writing the keyword in your caption tells people what to type, which is exactly what it is for. It does not set anything off by itself.
A like, a save, a share or a view. Instagram only tells us about three things: comments, messages, and taps on a button we have sent someone. Likes, saves, shares and views are not on that list, so none of them can start an automation, on a Reel or anywhere else.
Can you set it up before you post the Reel?
Yes, and it is the better way round. Most people build the automation after the Reel is already up, by which point it has been collecting comments that nobody answered.
When you create an automation, you choose what it watches:
| What it watches | What that means |
|---|---|
| Every post | Anything on the account, including things you post later |
| One specific post | A single Reel or post that you pick |
| Your next post | Whatever you publish from that moment on |
Your next post is the one to use for a Reel you have not uploaded yet. Set the automation up, publish the Reel, and it attaches to it. Choosing "every post" works too, it just casts a wider net.
What if you post the Reel first and it takes off immediately?
It still works, and the first comment is what tells us the Reel is there.
Instagram does not announce a new Reel to anyone. Nothing tells a tool the moment you hit publish, so the first sign a Reel exists is somebody engaging with it. If a comment arrives on a Reel we have not seen yet, an automation set to watch every post still answers it, and we go and fetch the Reel in the background so it shows up in your content library and you can point future automations at it directly. The very first person to comment on a brand new Reel gets their DM.
Do Reels and stories use the same automation?
No. They are two different kinds of automation, and the difference is where the person's message lands.
A Reel collects comments, which everybody can see. So the automation can reply out in the open and send a DM as well. A story collects replies, which are already private messages, so there is nothing public to reply to and the automation answers in the conversation the person just started.
Because they work differently, one automation does not cover both. If you want both, build two. Story reply automation has its own setup.
Does a Reel comment get a public reply as well as a DM?
It can, and on a Reel the public reply is the more valuable half.
The automation can post a reply under the comment and send the DM. Those do two different jobs. The DM reaches one person. The public reply is read by everybody scrolling the comments, and on a Reel that is mostly people who do not follow you, so it quietly tells the next hundred readers that a keyword exists at all. Writing a few different replies and letting them rotate stops the comments reading like the same sentence forty times over.
The DM itself is what Instagram calls a private reply, which is its own way of answering a public comment in the inbox. It comes with rules about timing, covered in how Instagram DM automation works.
How many DMs can a viral Reel send?
We do not put a limit on it. The only thing slowing it down is Instagram, which controls how fast messages can leave your account, so a Reel pulling in thousands of keyword comments in an hour goes out at Instagram's pace rather than ours. Instagram's DM limits covers what those are and what happens when you reach them.
The honest boundary: where this stops working
A comment only reaches your automation one way, and there is no backup. Instagram tells us the moment somebody comments, and that is the only way a comment gets in. Nothing goes back later to compare the comments sitting on your post against the ones that actually came through. So if a comment never reaches us, it is never answered, and it never shows up as a problem, because as far as the system is concerned nothing happened.
The most likely reason a comment never reaches us is your own comment settings. Instagram gives every account switches that quietly take comments out of circulation before any tool gets near them. Check these before you blame an automation:
- Hide unwanted comments, in Settings under Comments. This moves anything Instagram reads as spam or offensive into a hidden section.
SomeandMoreboth filter your comments.Nonedoes not. - Who can comment, which can limit commenting to a smaller group of people.
- Blocked accounts. In Instagram's own words, comments from somebody you have blocked are not visible to anyone but them.
Keyword comments are unusually exposed to the first one, and Reels are where it stings most. When a Reel does well, dozens of people type the same short word underneath it, and that is exactly the pattern spam filters are built to spot. If a Reel is sending far fewer DMs than the number of keyword comments you can count on the post, open that setting before you contact anyone's support team.
Two smaller things worth knowing:
If two automations could answer the same comment, the older one wins. The newer one silently does nothing. If a Reel stopped converting right after you added a second automation, that is where to look.
A keyword is matched anywhere inside a comment. Somebody does not have to type it on its own, which is what makes it forgiving of how people really write. The catch is that a short keyword hidden inside a longer word counts too, so a keyword trigger is worth picking carefully rather than at random.
What this changes for the Reel you are about to post
Build the automation first, set it to watch your next post, and put the keyword in the caption and on the last frame so people know what to type. Then the Reel goes up with its funnel already attached, instead of getting one after the comments have gone quiet.