LinkedIn Comment-to-DM Funnel: How to Build One
A comment-to-DM funnel turns one post into a machine: someone comments a keyword, gets a public reply, and receives the resource by private DM, automatically. Four things have to line up (a distinctive keyword, a document, a hook post, and a sender account) and the campaign must be wired before the post publishes, or early commenters sit in silence.
Run it when: you have a post worth reading and a resource worth sending.
Time: 30 minutes to wire, once the document exists.
Last reviewed September 2026.
Before you build the funnel
The document written, even as a private draft
A hook post drafted but not yet published
A sending account decided
The keyword checked against every other live funnel
How to build a comment-to-DM funnel on LinkedIn
1. Understand the chain before you build it.
Post with a comment CTA, someone comments the keyword, they get a public reply, then a private DM with a tracked link to the resource. Only comments trigger it. Nothing else in the system watches anything else.
2. Write the CTA in exactly one shape.
"Comment PLAYBOOK and I will send it over." A DM-style CTA, "DM me the word", breaks the funnel completely, because DMs are not watched. It also breaks the automatic keyword extraction from the post body, so the campaign cannot find its own trigger.
3. Choose a keyword that cannot hide inside other words.
Matching is a case-insensitive substring check against the whole comment. "AI" matches "wait", "email" and "again". "SEND" matches half of all comments. Pick one distinctive word, short enough to type on a phone, and check it against every other active funnel: two live funnels sharing a keyword send one commenter two resources from two senders.
4. [Make the document](https://app.reachium.io/documents?utm_source=sop&utm_campaign=linkedin-lead-magnet-funnel) first.
It does not need to be public. Delivery happens over a private per-lead link regardless, and editing the document later updates what already-delivered links show. SOP 21, How to Write the Lead Magnet Behind a LinkedIn Funnel covers what goes in it.
5. Wire the campaign before the post publishes.
One call binds post, keyword, document and sender together. Wire first, publish second, otherwise every early commenter sits in silence until somebody notices.
6. Attach a sender explicitly.
If you do not, the hook post's own publishing account gets attached when the post publishes, which is fine for an unpublished hook. A post that is already live, or one with no account bound, leaves the campaign with no sender and activation is refused.
7. Write the two messages, or let them generate.
The public comment reply is short and carries no link. The DM carries the tracked resource link. You can write both yourself, which is the better option when the brand voice matters, or let Reachium draft them from the post and the document. Either way, read them back before activating.
8. Know that an already-published post still works.
If the post went out through Reachium, you can wire it retroactively and the funnel enrols everyone who already commented the keyword, working through the backlog steadily. An engaged existing post is often the strongest hook available.
9. Expect a delivery lag for people who are not connected.
They get the public reply immediately and the DM once the connection exists.
The funnel auto-accepts their pending invitation rather than sending one, so it spends no invite capacity at all. Run it for a few weeks and you have a pool of warm first-degree connections that cost you nothing from the daily 25. This is by design, not a fault.
10. Watch two numbers after launch.
Keyword comments with no deliveries means the wiring is wrong. Lots of comments with low connection acceptance means the audience is not warm enough yet, and the answer is more personal posting before the next funnel.
Comment funnels: do this, not this
Do this | Not this |
|---|---|
"Comment PLAYBOOK and I will send it over" | "DM me the word PLAYBOOK" |
A distinctive keyword | "AI", "SEND", "YES" |
Wire the campaign, then publish | Publish and wire it afterwards in a panic |
Attach a sender deliberately | Assume one will be resolved |
One post, one funnel, one promise | Two live funnels sharing a keyword |
Deliver exactly what the post promised | Bait and switch, which kills the next funnel |
Rather not do the wiring? It is fiddly and the failure is silent: people comment and nothing arrives. Book a call and we build the funnel end to end.
You approve the campaign copy before anything sends.
Our inbox managers reply by hand, and they check with you first.
We hold the daily caps. 25 invites per account, no exceptions.
Month to month. No lock-in.
Questions people ask
How does a comment-to-DM funnel work on LinkedIn?
Your post asks people to comment a keyword. Each comment containing that keyword triggers a short public reply and then a private DM carrying a tracked link to the resource. Only comments trigger it. Nothing in the system watches DMs or reactions.
What keyword should I use?
One distinctive word, short enough to type on a phone. Matching is a case-insensitive substring check on the whole comment, so "AI" matches "wait", "email" and "again", and "SEND" matches half of everything. Check it against every other live funnel before you commit.
Can I add a funnel to a post that is already published?
Yes, if the post went out through Reachium. The funnel enrols everyone who already commented the keyword and works through the backlog steadily. An engaged existing post is often the strongest hook available.
Does a comment funnel use my daily connection request limit?
No. For commenters who are not yet connected, the funnel auto-accepts their pending invitation rather than sending one, so it spends no invite capacity. Run it for a few weeks and you have a pool of warm first-degree connections that cost nothing from the daily 25.
You are done when
Keyword chosen, checked for substring collisions, and identical in the post and the campaign
Document attached, or a delivery message written
Hook post linked, still unpublished if possible
Sender attached and confirmed
Both messages read back before activation
The funnel arms only when the post publishes, and someone is watching the first hour of comments
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