I’ve seen a bit of Substack’s tools in the 6 months I’ve been publishing here. Everyone is doing what they prefer, and that’s a perfectly valid strategy. Still, because Substack is also a social network, it helps to know what each option actually does.
What follows is my best understanding of the system. I didn’t design or code it, so treat this as informed observation, not a manual.
There are distinct ways to engage, and each sends a different signal, to the algorithm, to other writers, and to your own audience. Here’s the breakdown of what happens when you click.
Posting
Posting in itself is publishing your article to your publication. Posts are not featured in Substack’s social network, so your main path to propagation is enabling the checkbox to email it to your subscribers.
Sharing your post with a note
This is the first step you take to get the text out of your closed subscriber bubble. It goes outside to your followers. Followers, for writers who grew their account organically (as opposed to importing a list), are roughly 2x the number of your subscribers and usually include many of your subscribers but of course also a large number of people who don’t receive your emails.
Restacking (sharing your post or someone else’s)
Restacking is telling your followers that this is good content. The algorithm will show that activity to the author’s subscribers and followers, and you might get some new eyes for your work from this intersection.
When you’re a small account, sharing bigger accounts’ posts is strategic. When you’re sharing smaller accounts’ posts, you’re generous (and might I say, well read).
As Substack’s product lead put it: “Sharing, restacking and replying help boost your reach because they intersect audiences”.
Pro Tip: the restack logic - Not all restacks are equal. There is a strategic choice between a “Simple restack” and a “Restack with a note”:
The simple restack: This makes you a conduit. You are passing the spotlight directly to the author. It’s clean, generous, and drives traffic straight to them. Literally telling your followers to look there.
Restacking with a note: This makes you a curator. By adding your own commentary, you “gate” the attention. Your followers engage with your thoughts first. It builds your authority and keeps the social interaction (likes/replies) on your profile rather than just passing it along. Somewhat telling your followers why you decided to look there.
If you are trying to grow, restack with a note. If you are trying to encourage another writer, a simple restack is a pure, ego-free signal of support.
Commenting
When you comment on someone’s Note or post, your reply appears only under their content, whoever is looking has to open the post or note to see it. You’re engaging with the original author’s audience directly, not broadcasting to your own followers.
Even if the reach is smaller, commenting contributes to the original creator’s algorithmic boost by signaling “conversation, not passive consumption”. Posts with genuine back-and-forth outperform high-like, shallow content. But your own subscribers don’t get any special notification or feed placement of your comment just because you wrote it.
External sharing
When you distribute a Substack post to Facebook, Twitter, or elsewhere, you’re driving off-platform traffic. This doesn’t directly feed Substack’s internal algorithm, but it brings readers who might subscribe, restack, or comment, creating downstream signals that do.
The follower vs. subscriber split
This matters: your subscribers get your newsletter in their inbox. Your followers see your Notes in their feed but haven’t committed to email yet. When you restack or post a Note, it primarily hits that follower pool, which includes some subscribers. When you publish a full post, it hits subscribers’ inboxes only.
Case study: “The New Species”
My poem “The New Species”, published Feb 28, 2026, illustrates this split perfectly:
965 recipients (email subscribers who got it in inbox) but
35.37% open rate on the email (~ only 341 actual opens)
Yet, it had 23,952 total views, a 24.8x multiplier
85% of traffic from Substack internal
1,192 shares driving external and internal amplification
924 likes, 422 comments, 436 restacks
The email was just one entry point. The post lived and spread through Notes, restacks, and the discovery feed. Those 436 restacks and 1,192 shares carried it to audiences I’d have never reached directly. Meanwhile, the 422 comments built conversation under the post itself, signaling to the algorithm that this was content worth surfacing, but not broadcasting to my followers’ feeds the way the restacks did.
Some of you choose to comment on people’s notes and posts but not share them, some may do both, some (like myself) will share always but rarely comment. All are good ways to interact with people’s work. But know that your work will mostly be found via notes, yours and others, and that it’s views, comments, and notes that signal to the algorithm what’s worth propagating.
The one thing I would advise against, if you are still growing your account, is to only publish and be done. If you’re relying on your readers to spread the word out and they’re not as many, your work will remain enclosed in a bubble. The least you should do is share your post in a note. In fact, you should probably resurface some older posts in your notes too, from time to time.
The other thing I would advise to not do, is tag people on your own posts sharing notes to read them - unless you employ those folks, it’s rude and intrusive to order people into reading your own work.
And yes, however much I’d like my followers to subscribe me, there’s no denying they’re still helping me get my work out there, even if they shield themselves from my daily posts spam. Thank you, followers and subscribers, for putting up with me!
Do you have any hints? What’s your preferred way of socializing on the Sub?
You don't understand how badly my overthinking comes in to play when I'm trying to do anything on substack lol Thanks for sharing your insights!
I like the “conduit” vs “curator” insight. I’ll keep it in mind going forward! Thanks, Nicole.