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Looking for a Mailgun alternative?

Mailgun facts were verified on their own public pages on July 17, 2026 — their certifications are real, and we credit them.

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

Mailgun is established, certified infrastructure under Sinch: SOC 2 Type II, ISO 27001, AES-256 encryption at rest. The comparison turns on three words in that last item — under platform-held keys — and on what sits behind upper-tier gates: SSO and deliverability tooling. Email Fast hands key custody to you, ships the same deliverability engineering on every plan, and accepts your Mailgun SDK unchanged, so finding out costs a base URL.

The comparison

MailgunEmail Fast
Key custodyAES-256 at rest, platform-held keysorganizations can bring their own encryption keys — enroll, rotate, suspend, or revoke — and revocation fails closed: new sends are rejected and stored secrets become unreadable, to us included
CertificationsSOC 2 Type II and ISO 27001None yet — open security page
OwnershipSinchIndependent
Free tier100 emails/day2,500 emails/month, never expires
Paid entryBasic from $15/monthStarter, $9.90/month for 20,000 emails (pricing)
Tier gatingSSO and deliverability tooling on upper tiersSSO is enterprise-tier here too; deliverability engineering is not — every plan sends through the same infrastructure
Drop-in migrationSendGrid-, Mailgun-, and Postmark-compatible endpoints: point your existing SDK at a new base URL with a new key and keep your code

Keys, in practice

“Encrypted at rest” is table stakes; the question is who can decrypt. Mailgun's documentation answers it plainly: the platform. The other answer is the one we built: organizations can bring their own encryption keys — enroll, rotate, suspend, or revoke — and revocation fails closed: new sends are rejected and stored secrets become unreadable, to us included. Erasure follows custody, too: GDPR erasure by crypto-shred: destroying a key destroys the data it protected, without corrupting the tamper-evident audit ledger. More for security teams: enterprise.

Where Mailgun is the right choice

Switching

The Mailgun-compatible endpoint accepts your existing /v3/:domain/messages calls — swap the base URL and the key. 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. The full path: /migrate/mailgun.

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

Questions, answered plainly

Is Mailgun certified?

Yes: SOC 2 Type II and ISO 27001 per their site, under Sinch's ownership. Email Fast holds no third-party attestation yet — the security page says exactly which we lack, why we won't borrow badges, and what we ran instead — a 19-stage adversarial security review, run to zero confirmed findings. That review was internal and adversarial — a documented find→refute→fix→re-verify loop — not a third-party audit. We say exactly which one we have.

What does platform-held vs customer-held actually change?

Who can decrypt. With platform-held keys, the vendor encrypts and can always decrypt. With ours: organizations can bring their own encryption keys — enroll, rotate, suspend, or revoke — and revocation fails closed: new sends are rejected and stored secrets become unreadable, to us included.

Is Mailgun cheaper?

No — entry pricing now favors us: Mailgun's Basic starts at $15; our Starter is $9.90 a month for 20,000 emails. And on top of volume, contacts and subscribers are never billed — we price sending, not the size of your audience.

Do I have to rewrite my Mailgun integration?

No: SendGrid-, Mailgun-, and Postmark-compatible endpoints: point your existing SDK at a new base URL with a new key and keep your code. Existing /v3/:domain/messages calls work unchanged. The walkthrough: /migrate/mailgun.

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.