The best time to post on Substack: what 473,405 Notes say
We analyzed 473,405 Substack Notes from 3,034 creators. The best times are early morning ET and Mondays, but the honest finding is how little timing matters.
We analyzed 473,405 Substack Notes published by 3,034 creators over the last 12 months. The best time to post on Substack is early morning US Eastern time (midnight to 5am ET), and the best day is Monday, with weekends close behind. But the honest headline is the size of the effect: the worst posting hour gives a note an 18.1% chance of beating its author's usual numbers by 2x, and the best hour gives it 20.8%. Timing is real, and it is worth about three percentage points. What you write, how short it is, and how often you post all matter more.
As far as we can tell, nobody has published a Substack timing study from real posting data before. Buffer, Hootsuite, and the rest publish best-time guides for Instagram and X, but Substack has no public posting API, so the usual analytics vendors have no data to study. Eden indexes Substack alongside five other platforms for its Discover research feed, which is the corpus this study runs on. Here is everything we found, including the parts that undercut the premise.
Key findings
- Notes posted at midnight ET break out 20.8% of the time, the best rate of any hour.
- Notes posted between 8pm and 10pm ET break out 18.1% of the time, the worst rate of any hour.
- Monday is the best day to post on Substack Notes (19.9% breakout rate) and Friday is the worst (18.8%).
- The entire gap between the best and worst posting hour is about 3 percentage points.
- Notes under 100 characters break out 24.2% of the time, versus 14.1% for notes of 600 to 1,199 characters, so length moves outcomes three times as much as timing.
- Creators who post 3 or more notes a week see about 20% breakout odds per note, versus about 18% for creators posting less than once a week.
- The quiet-hours advantage belongs to accounts under 10,000 followers; accounts over 100,000 break out more often in the busy hours.
A breakout, throughout this study, is a note that earns at least 2x its own author's median likes. The full method is below.
How we ran it
- Sample: 473,405 Substack Notes from 3,034 creators tracked in Eden's index, published between August 2025 and August 2026. Every note was at least 7 days old at measurement time, so like counts had settled.
- Metric: each note's like count divided by the same author's median likes. We call a note a breakout when it earns at least 2x its author's median. Measuring against each author's own baseline means a 300-follower writer's hit counts the same as a 300,000-follower writer's, and it prevents a few celebrity accounts' habits from becoming "the best time."
- Timezone: all times are US Eastern (ET). Substack doesn't expose authors' timezones, and the platform's audience is heavily US-based, so ET is the least-wrong single clock. If your audience lives elsewhere, shift the tables to your audience's morning.
- Overall shape: the median note in the sample earned 10 likes, the top 10% crossed 108, and about 1 in 10 notes reached 100 or more.
The best hours to post
Breakout rate by publish hour, across all seven days:
| Hour (ET) | Notes | Breakout rate |
|---|---|---|
| 12am | 9,156 | 20.8% |
| 1am | 9,868 | 20.6% |
| 2am | 11,438 | 19.6% |
| 3am | 12,917 | 19.7% |
| 4am | 13,592 | 20.5% |
| 5am | 15,339 | 19.3% |
| 6am | 18,953 | 19.5% |
| 7am | 23,891 | 18.8% |
| 8am | 29,179 | 18.8% |
| 9am | 32,634 | 19.5% |
| 10am | 34,065 | 18.9% |
| 11am | 32,359 | 18.8% |
| 12pm | 31,363 | 19.5% |
| 1pm | 28,254 | 19.5% |
| 2pm | 26,181 | 19.5% |
| 3pm | 24,336 | 19.8% |
| 4pm | 22,636 | 19.6% |
| 5pm | 19,932 | 18.8% |
| 6pm | 16,887 | 19.3% |
| 7pm | 14,548 | 19.3% |
| 8pm | 13,535 | 18.1% |
| 9pm | 12,335 | 18.1% |
| 10pm | 10,637 | 18.5% |
| 11pm | 9,370 | 20.1% |
Two patterns stand out. First, the quiet hours win: midnight to 5am ET, when the fewest notes are published, carry the best breakout odds. Notes posted at midnight ET compete with about a quarter of the volume that 10am notes face (9,156 vs 34,065 in our sample), and the feed appears to reward the breathing room. Second, US evenings lose: 8pm to 10pm ET is the worst window in the table, which is when a day's accumulated notes are all still fighting for attention.
The overnight-ET edge probably isn't Americans posting at 2am. Midnight to 5am ET is 5am to 10am in the UK and 6am to 11am in central Europe, so a good chunk of this window is European writers posting in their morning, landing in a feed that US volume hasn't flooded yet. The practical translation for a US writer is early morning, not late night: schedule for 5am to 6am your time rather than staying up.
The best days to post
| Day | Notes | Breakout rate | Median vs own baseline |
|---|---|---|---|
| Monday | 71,930 | 19.9% | 0.84 |
| Tuesday | 73,216 | 19.4% | 0.81 |
| Wednesday | 72,550 | 18.9% | 0.80 |
| Thursday | 70,827 | 18.9% | 0.79 |
| Friday | 68,036 | 18.8% | 0.78 |
| Saturday | 57,552 | 19.6% | 0.83 |
| Sunday | 59,294 | 19.7% | 0.82 |
Monday is the best day, and performance decays through the workweek to a Friday low. Then the weekend recovers: Saturday and Sunday post the second- and third-best numbers on notably lower publishing volume. The two edges in this table are the same edge: post when attention is refilling and the feed isn't crowded, either at the start of the week or on the weekend days most writers skip.
The strongest pockets in the day-by-hour grid (each with thousands of notes behind it): Thursday 12am to 3am ET at 21.6%, Tuesday 12am to 3am at 21.4%, Monday 3am to 6am at 21.4%, and the one non-morning standout, Sunday 12pm to 3pm at 21.2%. The weakest: Saturday and Wednesday 9pm to midnight at about 18.2% to 18.3%.
Does the best time depend on your follower count?
Yes, and this is where the quiet-hours advice earns its fine print. We split the sample by each author's follower count at the moment they posted (our index records it with the note, covering over 99.9% of the sample), then compared the quiet window against the rest of the day within each band:
| Followers when posting | Notes | Breakout rate | Quiet hours (12am to 6am ET) | Rest of the day |
|---|---|---|---|---|
| Under 1,000 | 113,749 | 19.3% | 19.9% | 19.2% |
| 1,000 to 10,000 | 199,938 | 17.2% | 19.5% | 16.9% |
| 10,000 to 100,000 | 130,834 | 21.0% | 20.0% | 21.1% |
| 100,000+ | 28,932 | 25.8% | 23.1% | 26.3% |
The pattern flips with size. Accounts under 10,000 followers get the real quiet-hours edge, and for the 1,000 to 10,000 band it is the biggest timing effect in this entire study: 19.5% in the quiet window against 16.9% the rest of the day, a 2.6-point gap. Accounts over 10,000 do slightly better in the busy hours, and accounts over 100,000 clearly so (26.3% vs 23.1%). The likely mechanism: a big account's notes reach its own subscribers no matter how crowded the feed is, so it wins by posting when its audience is awake, while a small account depends on the open feed, where breathing room matters most. So the timing tables above are advice for accounts under 10,000 followers, which is most writers; past that, post when your readers are online and stop optimizing for the feed.
The finding that matters more: timing is small
If you read only one section, read this one. The full spread between the best and worst hour of the week is about three percentage points of breakout probability. Meanwhile, in the same dataset:
- Note length moves the needle three times as much. Notes under 100 characters break out 24.2% of the time; notes of 600 to 1,200 characters, 14.1%. That is a 10-point spread against timing's 3.
- Cadence compounds. Creators posting 3+ notes a week see about 20% breakout odds per note, versus about 18% for less-than-weekly posters, and they take the bet several times as often.
Both findings, and the strategy they add up to, are unpacked in how to grow on Substack Notes. The one-line summary of this entire study: pick a sensible slot in a quiet window, then spend your remaining energy on the note, not the clock.
How to act on this
- Schedule your notes into the quiet windows: early morning your audience's time, Mondays, and weekends. Don't wake up at 5am for a three-point edge; schedule Substack Notes instead, and Eden hands text notes to Substack's own scheduler so they publish with your devices off.
- Spend the saved attention on the note itself: short, or genuinely long, never the middle.
- Post at least three times a week. The per-note odds are stable, so more shots compound.
- Study your niche's breakouts, not the global averages: the Discover feed surfaces the notes that beat their author's baseline in your topic, which is this exact analysis running continuously per creator.
Frequently asked questions
What is the single best time to post on Substack Notes?
Early morning US Eastern time on a Monday, if you force us to pick one slot. Midnight to 5am ET carries the best breakout odds (up to 20.8% at midnight against an 18.1% floor in the evening), and Monday is the strongest day. For a US writer that means scheduling for roughly 5am to 6am local rather than posting live.
Does this apply to Substack articles and newsletters too?
No, this study covers Notes only. Long-form posts arrive by email, so their timing question is about inbox behavior rather than feed dynamics, and it needs open data we didn't analyze here. Eden schedules both notes and articles, but the tables above are feed data.
Do breakout rates differ by niche?
Almost certainly, and per-niche timing is the cut we plan to publish next; incumbent best-time guides publish one global average per platform precisely because they lack the per-creator data to go deeper. Until then, the safest per-niche signal is your own last 90 days of notes, or the breakout notes in your topic on Eden's Discover feed.
Does the best time to post change with follower count?
Yes. The early-morning quiet-window edge is real for accounts under 10,000 followers, and strongest between 1,000 and 10,000 (19.5% breakout in the quiet hours vs 16.9% the rest of the day). Above 10,000 followers the effect reverses, and accounts over 100,000 break out most in the busy hours (26.3% vs 23.1%), because their notes reach subscribers regardless of feed crowding.
Does posting through a scheduler hurt reach on Substack?
We have no evidence it does, and for text notes scheduled through Eden the question mostly dissolves: Eden hands the note to Substack's own built-in scheduler, so Substack publishes it exactly as if you had scheduled it there yourself. The mechanics are in how to schedule Substack Notes.
Where does this data come from?
From Eden's own social index, the same corpus that powers its research features across Substack, X, LinkedIn, Instagram, TikTok, and YouTube. For this study we took every indexed Substack note published in the 12 months to August 2026 that was at least a week old, 473,405 notes from 3,034 creators, and measured each against its own author's median likes. No third-party estimates, no surveys, no vendor data.
We built this study because we kept getting asked for a best time to post on Substack and every existing answer was a guess. If you want the same research running on your niche daily, plus scheduling that actually supports Substack, Eden's free plan includes 100 saved items and 50 AI credits with no card required. Start free.