"Comment LINK and I'll DM you" is the highest-converting call to action in creator marketing. It only works if the platform lets you automate the DM part.
In 2026, exactly one major platform does.
The capability table
| TikTok | |||
|---|---|---|---|
| Official comment-to-DM | Yes — Private Reply API | No | No |
| DM automation at all | Yes | Yes — Business Messaging API | No creator API |
| Messaging window | 24h standard, 7d via Private Reply | 48h from last interaction | n/a |
| Follow required | No | n/a | n/a |
| Account requirement | Business/Creator + FB Page | Verified Business + Advanced Access | n/a |
| Browser-tool enforcement | Not the model | Not the model | Active bans (2026) |

Instagram: the only supported comment trigger
Meta built a specific endpoint for this. Private Reply lets a business DM a commenter addressed by `comment_id` instead of `user_id`, and grants a 7-day window from the comment timestamp — regardless of whether that person follows you.
That last clause is why it matters. The standard messaging endpoint requires an open 24-hour conversation, which cold commenters do not have. Tools that use the wrong endpoint fail silently for exactly the audience you most want to reach.
Requirements: an Instagram Business or Creator account linked to a Facebook Page. Personal accounts cannot use API automation at all.
TikTok: automation yes, comment triggers no
TikTok's Business Messaging API is real and official — welcome messages, keyword replies, suggested questions, chat prompts. The window is 48 hours, genuinely more generous than Instagram's standard 24.
But every one of those automations responds to a conversation the user started. There is no comment-to-DM endpoint.
The practical workaround is not automation: you pin a comment saying "DM me PRICE", and your welcome message plus keyword replies take over once they do. That converts worse than a direct comment trigger, because you have added a step.
Full detail in TikTok DM Automation in 2026.
LinkedIn: no path, and active enforcement
LinkedIn has no creator messaging API comparable to Meta's, and in 2026 it ran an enforcement wave against tools that simulate browser sessions — HeyReach lost its integration in March.
There is no compliant way to build comment-to-DM on LinkedIn today. Anything offering it is driving a browser session with your credentials, which is the architecture LinkedIn is actively terminating. See the crackdown breakdown.

What this means for your funnel
If comment-triggered link delivery drives your revenue:
- Build the trigger on Instagram, where it is officially supported
- Use TikTok for reach, routing people to DMs with a pinned instruction
- Grow LinkedIn through publishing, not outreach tooling
- Close on WhatsApp if you sell to Indian buyers
For Indian creators specifically, the pairing that works is **Instagram to capture, WhatsApp to close** — because that is where money actually changes hands. More on that in the WhatsApp Business API guide.
The honest summary
One platform supports this properly. Building your primary funnel anywhere else in 2026 means either doing the DM step by hand, or using tooling that puts the account at risk.
StackPicks AutoDM does Instagram comments, story replies and Live, plus WhatsApp Business in beta. TikTok is on the roadmap when the official API supports what we would need. See the product.