Bluesky vs Substack Notes

My Medium friends can read this over on Medium.

People search for "Bluesky vs Substack" a lot. I didn't expect that at all, because on the surface, they don't really seem to compare that much.

But the searches are there. I can see them in my Search Console.

And after some thought, I get why. While Substack is prominent for the writing and newsletter aspect, it is increasingly becoming and booming as a social media platform with Notes, video inclusion, live streams, and podcasts. That rivals many other social media networks. Including Bluesky.

And those two, Substack and Bluesky, have something unique. Both promise the same thing to writers: a text-first feed without the noise, a place where a post can still find readers. With all the algorithms, ads, and crap of Twitter, Instagram, Facebook, and co.

Still, they are not the same kind of thing at large. Bluesky is "only" a social network. Substack is a newsletter platform with a social feed bolted on.

So the comparison really is: Bluesky vs. Substack Notes.

I have both. I don't use either one much, actually. More on that later.

Bluesky

Bluesky looks like early Twitter, and I wrote that when it opened up in 2024. That's the appeal. Twitter without the crap.

Chronological feeds, custom feeds you can build yourself, an open protocol underneath. It was the place everyone ran to after the US election. Nearly 46 million registered accounts by now.

Registered. Active is a different number. But Bluesky is not small, and if anything it is the only real Twitter rival that has some numbers to back it up. Other than… Substack Notes.

However, Similarweb counted about 10 million monthly active users on the mobile Bluesky app in June, down 27 percent from a year earlier, and around 3 million daily users in July. The quarterly average went from about 22 million at the end of 2024 to under 11 million now. Roughly half of the peak.

Half of the peak. In eighteen months.

The founder stepped down as CEO in March, and an ex-Automattic guy runs it for now. The company says the app is only one part of the plan, the protocol is the real product. Might be true. For a writer looking for readers, the app is the part that matters, though.

What Bluesky still has going for it, and it's a big one: it does not punish links. X does, Musk said so himself. On Bluesky, a post with a link to your article travels like any other post. Publishers noticed that early. The Boston Globe reported three times the traffic from Bluesky compared with Threads, back in late 2024. That was peak Bluesky. Fewer people are there now to click.

My own experience: I used to auto-post to Bluesky. I want to like it. But I don't have much hope, to be honest. Also, I don't put enough energy into it.

Substack Notes

Notes launched in April 2023. Which is really not that long ago. Feels longer.

Short posts, restacks, replies. It lives inside the Substack app and on the website, and every person you meet there already has a Substack account. That's huge.

Substack's numbers for it are big-ish. Co-founder Hamish McKenzie said last fall that the app drove over 32 million free subscriptions and nearly half a million paid ones in three months, and that the app is now the top source of subscriber growth for publishers. Bigger than recommendations. Notes is a big part of that app.

It's not my top driver anymore. Because I don't want to rely heavily on social feeds. My biggest growth factor is SEO. And that's hugely underrated on Substack. Another story, though.

Notes used to be big for me, though. In 2025 the app was my top source of new subscribers. Then I looked closer. The people who like a Note are not always the people who open an email. Rarely, actually. A Note can get a few hundred likes and the article that week gets fewer reads than that. So my view cooled a bit. Notes is good at staying in touch with the readers you already have. Not so much for finding new ones. Retention, not discovery. Followers != subscribers != readers.

Small things: no clickable hashtags, by design. Native scheduling arrived this spring. And the feed loves Notes about Substack itself. You'll notice that quickly. So the same issues that bug the big social networks will eventually (or already) bug Notes.

Same format, different job

A short post is a short post. But the two feeds do different jobs for a writer.

Bluesky gets your link in front of people who have never heard of Substack. Journalists, tech people, a political crowd, at least that's how it feels in my feed. Nobody is a subscriber there. They are readers, if the link works.

Notes gets your post in front of people who already read newsletters and are one tap away from subscribing to yours. That's a much shorter path. It's also a much smaller world.

Bluesky sends readers away from itself. Notes keeps them inside.

Which one is better depends on what you're missing. New readers? Bluesky, in theory. But just in theory. Subscribers from readers you already reach? Notes. More likely.

Downsides

Both feeds are short-lived. A post lasts a day, maybe less. Stop posting for a week and you start over. That's how these feeds work, and it means the growth only lasts as long as you keep feeding them.

Bluesky is shrinking now. That's the biggest one. It might stabilize, it might not. Betting a big part of your time on a network that lost half its active users would make me nervous. And there is no built-in way to earn anything there. It's a link out, and that's it.

As much as we don't like it, if growing a real social following is the goal, then Twitter beats Bluesky by a long shot.

Notes is a closed loop. Only Substack users see it (for now), and Substack decides what gets shown (somewhat). Followers are not subscribers, and Substack counts them separately for a reason. The feed is designed to keep you scrolling, same as every other one. I catch myself doing it. Mostly Notes is designed to keep you in the Substack app. Because what Substack really wants is that you don't use your email app and service for the newsletters, but the app. And I believe, eventually they will actually shut down the "open" email list option where you can take subscribers with you. Just like Medium did a while ago. Then, you'll be stuck inside Substack.

Also, in the end, both platforms, Bluesky and Substack Notes, take time away from the thing that keeps working when you sleep: the article itself. Search traffic keeps coming a year later. A Note doesn't.

That's why SEO is much more important than any social feed.

The Bottom Line

If you write a newsletter, Notes first. Logically. It's the same audience, one tap from subscribing, and it's where text-first writers hang out right now.

Bluesky could serve as a backup. If you want to invest some time in it. Post your links there, it costs little and links are welcome. Just don't expect too much.

And me? I post an article, I post a Note about it, an auto-post used to go to Bluesky (I might try that again), and I go back to writing. I am just not a short post guy. Not a social media guy, in general. Maybe you are. Then Notes is the better bet for now, I'd say.

If you're not already, follow me on Medium.

Get PROSTACK