How to Cross-Post from Mastodon to Substack Automatically

Post natively on Mastodon and Ferryman automatically syncs every new post to Substack — no copy-paste, no workflow change. Set up in under two minutes.

Start cross-posting free

Why cross-post from Mastodon to Substack

Mastodon and Substack reach genuinely different audiences. Mastodon is federated, instance-driven communities — strong technical, academic, and open-source presence. Substack, by contrast, is newsletter readers, paid subscribers, independent writers, and high-intent followers who want deeper context than a social feed usually provides.

Substack Notes lets newsletter-first creators stay visible between essays and turn short social posts into subscriber touchpoints. If you're already putting in the effort to write good posts on Mastodon, there's no reason that work shouldn't reach a Substack audience too — except that maintaining two presences manually is exhausting and easy to abandon. That's the problem Ferryman exists to solve.

Key differences between Mastodon and Substack

Cross-posting isn't just a copy-paste. The two platforms have different limits and conventions, and Ferryman handles each difference so you don't have to think about it.

Capability	Mastodon	Substack
Character limit	500	10,000
Images per post	4	10
Alt text on images	Yes	No
Video support	Up to 1:00	Up to 10:00
Native threading	Yes	No

Substack's 10,000-character limit gives you 9500 more characters than Mastodon's 500. Posts that fit on Mastodon always fit on Substack.

What gets synced

Original posts (replies and quote posts are off by default and can be enabled)
Images up to 10 per post, with alt text added where supported
Videos up to 600-second length on Substack (Creator plan)
Links — Ferryman preserves URLs and link cards where Substack supports them
Hashtags and mentions are preserved as-is; platform-specific mention syntax is rewritten
Posts fit Substack's 10000-character limit without splitting

Set up Mastodon → Substack cross-posting

Sign in to Ferryman with your X account. This is how Ferryman authenticates you — you can still set Mastodon as your origin platform afterwards.
Go to Settings and connect your Mastodon account. This is the platform you'll post on natively.
Connect your Substack account in Settings. See the Substack integration guide for the exact steps.
Set Mastodon as your origin platform and check Substack as a target. Toggle cross-posting on, and Ferryman will sync new Mastodon posts to Substack within a few minutes.

Edge cases worth knowing

Skip a specific post: include #noferry anywhere in your Mastodon post and Ferryman won't sync it to Substack.
Replies and quote posts: off by default. You can enable them in Settings if you want your Mastodon conversations to appear on Substack too.
Threads on Mastodon: Substack doesn't have native threading, so Ferryman joins thread parts into a single longer post where it fits.
Editing or deleting: Ferryman doesn't propagate edits or deletions automatically. Each platform keeps its own copy once posted.
Scheduling: Use Ferryman's planner to schedule a post and Ferryman publishes to Mastodon and Substack at the same time.

Manual cross-posting vs. Ferryman

Task	Manual	Ferryman
Cross-post a new Mastodon post	Copy text, re-upload images, rewrite mentions	Automatic, within minutes
Handle character-limit differences	Rewrite or split by hand	Posts fit Substack's 10000-character limit without splitting
Preserve alt text on images	Retype every time	Added where supported
Skip specific posts	Remember to not cross-post	Add #noferry and you're done

Frequently asked questions

How long does it take for a Mastodon post to appear on Substack?

Ferryman checks for new Mastodon posts every few minutes and syncs them to Substack as they arrive. Most cross-posts go live on Substack within five minutes of the original Mastodon post.

What happens if my Mastodon post is too long for Substack?

Substack's 10,000-character limit gives you 9500 more characters than Mastodon's 500. Posts that fit on Mastodon always fit on Substack.

Are images and videos preserved when cross-posting from Mastodon to Substack?

Yes. Images attached to your Mastodon post are uploaded to Substack automatically, up to Substack's limit of 10 per post. Videos are preserved when both platforms support them (Creator plan).

Can I cross-post one Mastodon post but skip another?

Yes. Include #noferry anywhere in a Mastodon post and Ferryman will skip syncing it to Substack (and any other connected platforms).

Does Ferryman cross-post my Mastodon replies and quote posts?

By default, only original posts are cross-posted. You can opt in to syncing replies, quote posts, or reposts from your Ferryman settings.

Is cross-posting from Mastodon to Substack free?

Every account starts with a 7-day free trial, so you can try cross-posting between Mastodon and Substack before you're billed. Cancel anytime before the trial ends and you won't be charged.

Related cross-post guides

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