SMTPy vs SimpleLogin: The Definitive Comparison for 2026

Email aliasing is booming, driven by growing awareness of privacy issues. Two solutions stand out: SimpleLogin, a pioneer acquired by Proton in 2022, and SMTPy, an open-source self-hosted alternative. This comparison will help you choose based on your needs.

At a Glance

Criteria	SMTPy	SimpleLogin
Hosting	Self-hosted (your server)	Cloud (Proton servers)
Custom domain	✅ Yes (all plans)	✅ Yes (paid)
Built-in mailbox	✅ Yes (read, reply, forward)	⚠️ Partial (reply from alias)
Open source	✅ Yes (100%)	✅ Yes
Free plan	1 domain, 5 aliases, 100 emails/mo	10 aliases, no custom domain
Paid starting price	€9/month	€4/month (30 aliases)
Unlimited aliases	✅ Pro plan (€9/mo)	✅ Premium plan
API	✅ Full REST + API keys	✅ Available
Data sovereignty	✅ Your server or France	⚠️ Switzerland (Proton)

Hosting and Privacy

SimpleLogin is owned by Proton since 2022. Data is hosted in Switzerland with a strict privacy policy. It is a good option if you trust the Proton ecosystem.

SMTPy is self-hosted: you install the service on your own VPS or dedicated server. Your data never passes through a third party. If you use smtpy.fr, the service is hosted in France, subject to French law and GDPR.

Custom Domain

SimpleLogin offers custom domains from the Premium plan. SMTPy includes custom domains on the free plan — it's actually its core design principle.

Built-in Mailbox

This is where SMTPy stands out: it offers a real web mailbox for reading, replying, forwarding, and composing emails directly from the interface. SimpleLogin allows replying from an alias (by replying to the forwarded email), but without a dedicated messaging interface.

Pricing

SimpleLogin is cheaper at entry level (€4/month for 30 aliases) if you don't have a custom domain. SMTPy becomes more competitive once you have multiple domains or professional usage.

When to choose SMTPy?

• You want to use your own domain for aliases
• You want to self-host your email service
• You need a full mailbox to reply from your aliases
• You're building applications and want a powerful API
• Data sovereignty is a priority

When to choose SimpleLogin?

• You want a turnkey service without server administration
• You already use the Proton ecosystem (ProtonMail, ProtonVPN)
• You want aliases on shared domains (simplelogin.com)

See also: Full SMTPy vs SimpleLogin comparison · Complete guide to email aliases