Connection settings
| Host | smtp.eusend.dev |
| Port | 465 — implicit TLS, encrypted from the first byte. STARTTLS on 587 and plain SMTP on 25 are not supported. |
| Username | The literal string eusend — not your email address. |
| Password | Any eusend API key. A eu_test_ key works here too, so you can wire a platform up without delivering anything. |
The username catches most people once: it is always the word eusend, and the key goes in the password field. Swapping the two is the usual cause of a 535 authentication failure.
Not a bypass around the safeguards
SMTP submissions join the same queue as API sends and are subject to the same rules. Your domain still has to be verified. Suppressed addresses are still dropped. Daily and monthly limits still count. The only practical difference is that an SMTP message has nowhere to carry per-send flags, so tracking follows your organization default rather than a value on the request.
Ready-made setup guides
Same four settings everywhere — only the location of the settings screen changes. There are step-by-step guides for the platforms people ask about most:
- WordPress and Ghost — replace the host’s unreliable
mail()with a real relay. - Supabase Auth — get confirmation and magic-link mail off the shared default sender and onto your own domain.
- Django, Laravel, Rails — a few lines of framework config.
- Nodemailer and PHPMailer — for everything that rolls its own transport.
When to use the API instead
SMTP is the right answer for software you don’t control. For code you do, the REST API gives you things the protocol can’t: an idempotency key so a retry doesn’t double-send, a message ID returned synchronously, scheduling, batch sends, and per-send tracking flags. Nothing stops you using both — many accounts run the API from their product and SMTP from their CMS.
Create an account, verify your domain, and paste the host, port, username, and key into whatever you're already running.
Create a free account