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Looking for a Substack alternative?

Substack facts were verified on their public pages on July 17, 2026 — including the discovery network we can't match.

Facts verified 2026-07-17 — corrections: hello@emailfast.dev

Substack's discovery network drives real subscriber growth — that's their headline claim, and the honest reason to be there. The price: 10% of your paid-subscription revenue, plus payment processing, on delivery Substack itself runs through a third party (Mailgun). Email Fast makes the opposite bets — you keep your revenue and we run our own pipes — and we have no discovery network to offer you.

The comparison

SubstackEmail Fast
Cost to publishFree; 10% of paid-subscription revenue plus payment processingPriced by sending volume (pricing); no revenue share
GrowthA discovery network that drives real subscriber growthNone — growth is yours to earn
DeliveryRuns on a third-party provider (Mailgun)Email Fast runs its own mail transfer agent, warmup engine, reputation breaker, and per-tenant fair queue — the pipes are ours, not resold
Developer surfaceNo developer API surfaceSDKs for the browser (EmailJS-compatible), Node.js, Python, PHP, Go, and Ruby, plus a zero-dependency CLI and a published OpenAPI specification
Security pageNone found at verificationOpen security page

The 10%, in numbers

At $50,000 a year in paid subscriptions, 10% is $5,000 a year, every year, before payment processing. Here, reader billing runs through Stripe and we charge for sending volume — your cost scales with how much you send, not how well you monetize. Newsletters with a public archive and RSS feeds are on every plan. Honesty requires the other side stated plainly: reader billing opens with general availability, and the discovery network you'd be leaving is real.

Where Substack is the right choice

Switching

Export your subscriber list and bring it over — contacts and subscribers are never billed — we price sending, not the size of your audience. Archive and RSS are built in, and consent-first growth comes with it: hosted signup forms with double opt-in through our own delivery path, so every subscriber carries verifiable proof of consent. Start with a sandbox key: sandbox keys (ef_sandbox_…) that run the real pipeline dry: real validation, real rendering, real events, a hosted capture inbox — and no email leaves. Live delivery opens at launch; reader billing opens with general availability.

Substack is a trademark of its owner; Email Fast is not affiliated with or endorsed by them. Facts about Substack were verified on their public pages on the date above — corrections: hello@emailfast.dev.

Questions, answered plainly

Does Email Fast have anything like Substack's discovery network?

No, and we won't pretend a feature list substitutes for one. Discovery drives real subscriber growth — it's Substack's headline claim and the best reason to choose them. If you leave, you take over growth yourself; what we provide toward it is hosted signup forms with double opt-in through our own delivery path, so every subscriber carries verifiable proof of consent.

Who actually delivers Substack's email?

A third-party provider — Mailgun. It's a pattern in this genre: every newsletter platform we surveyed rents its delivery: beehiiv's status page lists SendGrid components; Buttondown's subprocessor list names Mailgun and Postmark; Substack sends through Mailgun (verified on their own public pages, July 2026).

Can I run a paid newsletter on Email Fast today?

The platform is built for it — public archive, RSS, and paid subscriptions with reader billing through Stripe — but reader billing opens with general availability, and live delivery opens at launch. Today you can build and test everything against a sandbox key.

What does the 10% add up to?

Plain arithmetic: $50,000 a year in paid subscriptions pays Substack $5,000 that year, before payment processing. Our pricing is volume-based and published: pricing.

See it for yourself

Sandbox keys run the real pipeline dry — real validation, real events, a hosted inbox, no email sent. Early access is onboarding now.