SMTPy vs Addy.io — overlap, differences, and when to pick which.
Addy.io (formerly AnonAddy) is the open-source aliasing service most often recommended for self-hosters. SMTPy and Addy.io have heavy overlap; the differences matter mostly when you want a stored inbox, team features, or a transactional-send API.
| Feature | SMTPy | Addy.io |
|---|---|---|
| Unlimited aliases | ✓ | ✓ (rate-limited on free) |
| Custom domains | Up to 100 | Up to 20 (Pro) |
| Stored inbox (read messages in UI) | ✓ Full inbox | — Forwarding only |
| Browser extension | — (planned) | ✓ All major browsers |
| Mobile app | — (planned) | ✓ iOS / Android |
| Self-hostable | ✓ | ✓ (open-source) |
| Open source | Private (today) | ✓ Fully open |
| Transactional send API | ✓ | — |
| Outbound webhooks | ✓ | — |
| Shared inbox for teams | ✓ | — |
| Pricing | Free / €9 / €29 | Free / $1 / $3 |
When to pick which
Pick Addy.io if you want a fully open-source stack, the cheapest paid tier, or a polished mobile-first experience for individual privacy use. Pick SMTPy if you need a stored inbox, team features, or a transactional-send API in the same product.