ReachleeHow to automatically message people
who comment on your Facebook post.
Two working setups, step by step: the free Comment to message automation inside Meta Business Suite, and Reachlee for keyword triggers on any post, links, lead capture and follow-ups. Plus what the commenter sees and the Meta rules that decide whether your message lands.
The short answer
To automatically message someone who comments on your Facebook post, you need a Facebook Page (not a personal profile or a Group) and one of two tools. Meta Business Suite includes a free Comment to message automation that sends one fixed Messenger reply when a comment contains a keyword. Reachlee connects to the same Page through Meta's official Messenger Platform and adds keyword triggers across one, several or every post, links and buttons, a public comment reply, email or phone capture, and one follow-up reminder. Either way, Meta allows exactly one private reply per comment, sent within 7 days of the comment.
Prerequisite: a Facebook Page, not a profile or Group.
Everything here runs on Meta's Messenger Platform, which works with Facebook Pages only. A personal profile, even in professional mode, cannot receive comment webhooks or send Messenger messages through the API, so no tool can automate it. Groups are out too: the Groups API was withdrawn. If your audience lives on a profile or in a Group, create a Page (free, minutes) and post there. Page tokens don't expire on a 60-day clock the way Instagram tokens do, so a connected Page rarely needs reconnecting. The Instagram equivalent is our comment-to-DM tutorial; one Reachlee workspace holds both channels.
- A Facebook Page you administer, with permission to perform the messaging task on it.
- For the free path: a desktop browser. Comment to message cannot be set up from the Business Suite mobile app.
- For Reachlee: a Google login and about five minutes. Pages count toward your connected-account limit like Instagram accounts (Free 1, Pro 3, Business 10).
Path A: Meta Business Suite's free Comment to message.
Open Business Suite on desktop
In a desktop browser, open Meta Business Suite, select the Page, then Inbox → Automations. You'll see Instant reply, Away message, Frequently asked questions, Comment to message and Custom keywords. The last two are desktop-only to set up.
Pick your keywords
Choose Comment to message and enter the keyword(s). The keyword rules are strict: up to 5 keywords, matched case-sensitively, and each keyword usable in only one automation. Covering "link", "Link" and "LINK" costs three of your five slots.
Write the one reply
Business Suite sends one fixed short text reply. There is no second message, follow-up, email or phone capture, Google Sheets, carousel or per-post analytics. Write it to stand alone: the thing they asked for, or a plain question inviting them to write back.
Save, then wait 15 minutes
The reply goes out after a 15-minute delay unless you reply first, so a test comment will not produce an instant message. If the commenter needs to hear from you while still on the post, that delay is the first reason people move to Path B. The full list of constraints is in [Business Suite's comment-to-message limits](/guides/meta-business-suite-comment-to-message-limits/).
Path B: the step-by-step setup in Reachlee.
Connect your Facebook Page
Sign in with Google, click Connect Facebook, log in with Facebook and pick the Pages you administer. Reachlee never sees your password; Meta hands over a scoped Page token. Reachlee is a [Meta-verified tech provider](/meta-verified/).
Pick one post, several, or every post
Create an automation with the comment trigger and choose the scope. Every-post scope is the right default once comment-to-message is part of your content system, because future posts inherit it. Boosted Page posts are covered: Meta delivers comments on ad posts, so a boosted variant fires the same automation.
Set the keyword, or match any comment
Add the word people should comment: "LINK", "PRICE", "MENU". Matching is case-insensitive and you can list several. For giveaways you can match any comment instead, but keywords filter out congratulations and give the caption a clear call to action.
Write the Messenger reply, text first
Lead with text: the thing they asked for, the link, or a one-line question. Buttons and links go out as text first when they need to, so the one private reply Meta allows per comment always lands and the link is never the message that gets lost. Every link is tracked. This is your only private reply for that comment, so make it complete on its own.
Add an optional public comment reply
Turn on the public reply if you want "Sent you a message!" under their comment. It confirms something happened and teaches other readers that commenting gets a response. Reachlee rotates through a pool of replies so the thread doesn't read like one line pasted 200 times.
Optional: capture an email or phone, and add a follow-up
Inside the same thread, Reachlee can ask for an email and/or phone, validate the reply, save it to Contacts, retry once on a bad format and send a thank-you; on Business each contact syncs to Google Sheets. You can also add one follow-up reminder, sent at least 30 minutes later inside Meta's 24-hour window and cancelled the moment they reply or click. Follow-ups only fire after the person has written back, because a private reply alone does not open the window.
Publish
Flip it live. Every new matching comment gets the Messenger reply within seconds of Meta delivering it. If the post already has comments from the last 7 days, run Retrigger; it skips anyone already messaged.
Test from a different Facebook profile
Don't test as the Page or from the admin's own profile: the Page's own comments are ignored, so nothing fires. Have a friend or a second profile comment the keyword, then watch for the public reply and the Messenger message. If it doesn't arrive, work through [Facebook comment-to-message not working](/guides/facebook-comment-to-message-not-working/), which lists causes by how often they bite.
What the commenter actually sees.
A new Messenger thread with your Page opens, and Meta shows the message as a reply to their comment, so it reads as a response rather than cold outreach. If they write back, the 24-hour window opens and the conversation continues freely. If they never reply, the thread sits with your one message in it. One thing we have seen in practice: a brand-new Page's first private replies can land in the recipient's Message Requests or Spam folder until the Page has some conversation history, while established Pages deliver to the main inbox. That is observed behaviour, not a documented rule, but worth knowing when you test with a Page you created yesterday.
- A Messenger thread from your Page, shown as a reply to their comment.
- Their reply opens the 24-hour window; your message alone does not. See the Messenger 24-hour rule.
- New Pages: check Message Requests and Spam during testing. It resolves as the Page builds up conversations.
The rules Meta applies to both paths.
Private replies come with two hard limits that no tool changes. The message must be sent within 7 days from when the comment was created; older comments are permanently ineligible. And only one message can be sent to the person who commented, so that single reply has to carry everything, and if two automations match the same comment only one can win. After that, only when the person responds can you continue, inside the 24-hour window. Boosted posts follow the same rules. The wider rulebook is in Facebook Page automation rules.
- 7 days from the comment, then no private reply is possible.
- One private reply per comment, ever. Overlapping automations produce a loser, not two messages.
- The window opens when they reply, tap Get Started, click a Click-to-Messenger ad or open an m.me link. Your private reply does not open it.
- Comments on boosted and ad posts are delivered and handled like any Page post comment.
Make it convert once it's live.
Four habits that separate a working automation from a lead machine on a Facebook Page.
Put the keyword in the post copy
The automation only fires on comments, so ask for them: "Comment MENU and we'll send it in Messenger". Explicit keyword asks beat "link in the comments", which gets buried as the post takes off.
Make the single reply complete
You get one private reply per comment. Put the link, price or answer in it, then end with a one-line question. The question earns the reply that opens your 24-hour window.
Ask for the email inside the thread
A Messenger thread is a lead you can lose after 24 hours; an email is one you keep. The capture step asks, validates and saves without a landing page.
Set up ice breakers too
Commenters who open Messenger but don't type often tap a suggested question instead. Messenger ice breakers show up to 4 questions per Page, each answered automatically.
Set it up free on your Page.
Comment-to-Messenger is on the free plan: 1 connected account (Instagram or Facebook Page), full automation, no credit card. Pro ($9/mo, ₹499 in India) unlocks 3 accounts, every-post triggers, Retrigger and follow-ups. Growth ($14/mo) adds Reachlee AI with 1,000 credits. Business ($29/mo) adds 10 accounts, 5 team seats and Google Sheets.
Start freeFacebook comment-to-message, answered.
Can I auto-message people who comment on my personal Facebook profile?
No. Meta's Messenger Platform works with Facebook Pages only. A personal profile, even in professional mode, emits no comment webhooks and cannot send Messenger messages through the API, so no tool can automate it. The same goes for Groups, whose API was withdrawn. Create a Page and post there.
Why does the Business Suite reply take so long to arrive?
By design: Business Suite sends keyword-triggered replies after a 15-minute delay unless you reply to the person first. If you need to reach the commenter while they're still on the post, that delay is the main reason to use a Messenger Platform tool; Reachlee sends within seconds.
Does this work on boosted posts and ads?
Yes. Meta sends no webhooks for the ad post itself but does send them for comments on ad posts, so a comment on a boosted version of your Page post reaches Reachlee and fires the automation. Make sure the automation's scope includes the post being boosted, or use every-post scope.
How many messages can I send to one commenter?
One private reply per comment, within 7 days. You can continue only if the person responds, which opens the 24-hour window; inside it you can send freely, including promotional content and a follow-up. Outside it, only message tags for specific non-promotional updates and opted-in notifications are allowed.
Can I message people who commented before I set this up?
Within the last 7 days, yes. Reachlee's Retrigger runs an automation over a post's comments from the past week, skipping anyone already messaged. Older comments are ineligible under Meta's rule, so no tool can reach them; Business Suite cannot act on earlier comments at all.
Why did my test message go to Message Requests or Spam?
We have seen this with brand-new Pages: the first private replies from a Page with little conversation history can land in Message Requests or Spam, while established Pages deliver to the main inbox. It's observed behaviour rather than a published rule, and it fades as the Page has real conversations.
Is there a limit on how many private replies my Page can send?
Meta rate-limits per Page: 750 private replies per hour, up to 300 Send API calls per second for text messages, and a Business Use Case limit of 200 times the Page's engaged users per 24 hours. Reachlee reads Meta's rate-limit headers and backs off automatically, so a viral post paces itself instead of tripping throttle codes 32, 80001 or 80006.
Is this the same as Instagram comment-to-DM?
Same idea, different channel. On Instagram the equivalent private reply opens an Instagram DM; on Facebook it opens a Messenger thread from your Page. The Meta rules match (one reply per comment, 7 days), and Reachlee runs both from one workspace. The Instagram version is in the comment-to-DM use case.
Instagram