How the Substack Notes Algorithm Works in 2026 (And What It Actually Rewards)
The old playbook stopped working. Here’s the new one, straight from the algorithm’s creator.
If your Substack Notes growth stalled in the second half of 2025, you’re not alone.
And you’re not doing anything wrong. The Substack Notes algorithm changed.
From late 2024 through mid-2025, Notes was a growth bonanza. Some creators were adding thousands of subscribers per month. A single viral Note could bring in 50–100 new subscribers overnight.
Then it stopped. Growth rates dropped 50–75% for many writers. The same tactics that worked in January stopped working by July.
People assumed the algorithm was broken. It wasn’t broken. It was recalibrated.
Let me explain what happened, how the Substack Notes algorithm actually works now, and the daily system I use to drive consistent growth through the changes.
How the Substack Notes Algorithm Actually Works
Substack held an event in New York City where Mike Cohen, the head of machine learning and the person who literally built the Notes algorithm, explained how it works. And Hamish McKenzie, Substack’s co-founder, confirmed the company’s design philosophy.
Here’s what they said:
The Notes algorithm does not optimize for time spent on the platform. It does not optimize for ad clicks. It does not optimize for engagement metrics.
It optimizes for subscriptions.
The entire goal of the Notes feed is to connect readers with writers they’ll want to follow, and eventually pay. That’s fundamentally different from every other social platform.
LinkedIn wants you to keep scrolling so it can show you ads. Instagram wants you to stay in the app so it can sell your attention. TikTok wants you to consume endlessly to maximize ad impressions.
Notes wants you to find a writer worth subscribing to.
That’s why Notes works for creators. And it’s why the old engagement-hacking tactics stopped working. The algorithm evolved to filter out signals that didn’t actually lead to subscriptions.
Substack held an event in New York City where Mike Cohen, the head of machine learning, the person who literally built the Notes algorithm, explained how it works. And Hamish McKenzie, Substack’s co-founder, explained why they built it the way they did.
What Changed: The “Notes Bubble” Explained
The “Notes Bubble” (roughly October 2024 through June 2025) was inflated by several behaviors the algorithm has since deprioritized:
1. Mutual boosting circles
The old playbook was simple: boost your friends’ Notes, they boost yours, everyone grows. But the new ranking layer detects “saturation” — when the same people keep interacting with each other’s content, the algorithm starts discounting those interactions. It’s looking for genuine audience expansion, not closed loops.
2. Low-signal engagement
“Love this!” and “Great post!” comments used to count as engagement signals. Now the algorithm weights high-signal interactions: replies that add genuine value, thoughtful responses, substantive conversation. A two-word comment is nearly invisible to the current algorithm.
3. Format gaming
Some writers figured out that certain formats (listicles, hot takes, controversial opinions) got more reach. The algorithm has evolved to look at audience overlap and genuine interest alignment rather than content format. A well-crafted story Note now outperforms a formulaic listicle if the story reaches the right readers.
4. Follower-count bias
During the bubble, large accounts dominated the feed disproportionately. The recalibrated algorithm distributes more reach to smaller creators whose content genuinely resonates with their target audience. This is good news if you’re growing. The playing field is more level now than it was during the bubble.
The 5 Behaviors the Algorithm Rewards Now
Based on Substack’s own guidance, the data from my Notes activity, and what I’m seeing work for Academy students, here are the five behaviors that drive growth in the current algorithm:
1. Intersecting audiences 🤝
The algorithm looks for overlap between your readers and potential new readers. When someone who reads newsletters similar to yours engages with your Note, that’s a strong signal. It tells the algorithm: this writer’s content is relevant to an audience that doesn’t know about them yet.
What this means for you: engage with writers whose audiences overlap with yours, not just writers you’re friends with. Read in your niche. Reply to content in your niche. The algorithm maps your interaction patterns and uses them to determine who should see your work.
2. Value-adding replies ✍🏻
Your replies on other people’s Notes now matter more than your own standalone Notes in some cases. When you leave a thoughtful reply that adds genuine insight, the algorithm surfaces your name to that writer’s audience.
What a high-signal reply looks like:
Adds a data point, example, or perspective the original Note didn’t cover.
Asks a specific question that extends the conversation.
Shares a personal experience that validates or challenges the original point.
Is more than two sentences. Length signals effort and substance.
What a low-signal reply looks like: “Great post!” “So true.” “Love this.” These are invisible now.
3. Authentic restacking ♻️
Restacking other writers’ posts and Notes, with genuine commentary, is one of the most effective growth behaviors on the platform right now. But it has to be real. Restacking without commentary, or restacking in bulk without genuine engagement, gets filtered.
Substack’s own guidance states that “signal-boosting other publishers and joining the wider conversation are both linked to noticeable growth.”
How to restack effectively:
Add 2–4 sentences of your own perspective. Why does this matter? What would you add? Where do you agree or disagree?
Restack content from writers in adjacent niches, not identical ones. This introduces your profile to new audiences.
Restack consistently (1–2 per day), not in bulk.
4. Consistency over virality 🗓️
The compounding curve on Notes is real but slow. Months 1–3 show minimal reach. Months 4–6 show noticeable uptick. Months 7–12 show exponential growth on the same quality of content.
The algorithm needs data to learn who you are and who should see your work. Sporadic posting doesn’t give it enough data. Daily posting teaches it your patterns. The writers who post consistently for 6+ months have structural advantages that new accounts can’t shortcut.
5. Story-driven Notes 📖
The Notes that convert browsers into subscribers most effectively are not tips. They’re micro-stories. A personal experience. A specific moment. A lesson learned the hard way.
Why? Because stories demonstrate your voice, your perspective, and your lived experience; the three things a potential subscriber is evaluating before they click “Subscribe.” Tips can come from anyone. Your story can only come from you.
The Daily Notes System I Use
Here’s the exact system. 20–30 minutes per day. That’s it.
Morning (10–15 minutes):
Write 1–2 original Notes. Short. One idea each. Mix formats: one story-based Note, one tactical/insight Note.
Restack 1 Note from a writer in an adjacent niche with 2–4 sentences of genuine commentary.
Midday or evening (10–15 minutes):
Reply to 5–10 Notes from other writers with substantive responses. Not drive-by comments. Actual value.
Reply to comments on your own Notes. This creates threads, which signals active conversation to the algorithm.
Weekly addition:
I run a Notes Boost in my Chat community once per week. Not to game the algorithm, to build real relationships with other writers whose audiences overlap with mine. The genuine connections that form through these boosts drive more long-term growth than any tactical trick.
Tip: Block off 30-60 minutes every Monday morning to write out all of your notes for the upcoming week and save them as drafts. That way, you have a library of ready-to-go Notes you can quickly publish.
This system has driven consistent growth through every algorithm change. Not because it hacks the system. Because it’s aligned with what the system rewards: genuine connection, substantive content, and behaviors that lead to real subscriptions.
The full Notes playbook, including the specific Note formats that convert, the posting schedule I use, and the engagement system, is inside The Substack Bestseller Academy.
The Biggest Notes Mistakes to Avoid in 2026
Posting and ghosting ❌
If you spend 30 minutes writing a Note and 0 minutes engaging with other writers, you’re leaving growth on the table. Engagement is not optional. It’s how the algorithm learns who your audience is.
Chasing virality instead of building consistency ❌
A Note that gets 500 likes but zero subscribers is less valuable than a Note that gets 20 likes and 5 subscribers. Optimize for the right metric.
Copying what large accounts do ❌
Writers in the “how to grow on Substack” niche have a built-in advantage: their target audience is already on Substack looking for growth advice. Their reach numbers are not replicable across other niches. Take their strategic principles. Ignore their specific metrics.
Treating Notes as a broadcast channel ❌
Notes is a conversation platform. The algorithm can tell the difference between someone who posts and leaves and someone who participates. The people who participate grow.
FAQ: Substack Notes Algorithm
Does the Substack Notes algorithm optimize for engagement?
No. According to Mike Cohen, Substack’s head of machine learning, the Notes algorithm optimizes for subscriptions. It’s designed to connect readers with writers they’ll want to follow and eventually pay. This is fundamentally different from engagement-optimized platforms like LinkedIn or Instagram.
How often should I post on Substack Notes?
1–2 original Notes per day is the sweet spot. Combine this with 5–10 substantive replies and 1–2 restacks daily. Total time: 20–30 minutes per day.
Why did my Substack Notes growth slow down?
The Notes algorithm was recalibrated in 2025, deprioritizing mutual boosting circles, low-signal engagement, and format gaming. Growth now comes from intersecting audiences, value-adding replies, and authentic restacking.
Do Substack Notes actually drive subscribers?
Yes. Substack reported 32 million new subscriptions driven from within the platform in a single quarter. Notes is the primary discovery engine. Many creators report that Notes drives 50–70% of their total subscriber growth.
The full Notes playbook, including the specific Note formats that convert, the posting schedule I use, and the engagement system, is inside The Substack Bestseller Academy.
P.S. The writers who adapted to these changes are growing faster now than they were during the bubble. The bubble brought in email addresses. The new system brings in readers. There’s a difference.