Guides
Instagram's 24-hour messaging window, private replies and the 7-day human agent tag — explained
When a business can and can't message someone on Instagram, in plain English — and how to design automation around it.
By the GramForGrow team 5 min read
Instagram protects people from spam with a few simple rules for business messaging. Knowing them saves you from “why didn't my message send?” moments.
Rule 1: they have to go first
A business can't cold-DM people through the API. The conversation starts when someone messages you, comments on your post, replies to your story or mentions you.
Rule 2: the 24-hour window
Every time someone messages you, you get 24 hours to reply as much as you like — text, links, buttons, images. When the window closes, you wait for them to message again.
Rule 3: one private reply per comment
A comment isn't a message, so it doesn't open the 24-hour window. Instead you may send one private reply DM per comment, within 7 days. If they reply to it, the normal 24-hour window starts.
Rule 4: human agents get 7 days
Apps approved for the Human Agent permission may let a real person (not automation) reply for up to 7 days after the last message — useful for support cases that take time.
| Situation | Can you message? |
|---|---|
| They DMed you 3 hours ago | Yes — anything |
| They commented yesterday | Yes — one private reply |
| They DMed you 3 days ago | Only a human agent, if your app has the permission |
| They've never interacted | No |
Design tip
End every automated message with a question. When they answer, the window resets and your flow can continue.Enjoyed this? Get one useful email a month.