SocketLabs SMTP settings: smtp.socketlabs.com, port 587
SocketLabs SMTP relay: host smtp.socketlabs.com, ports 25/587/2525 STARTTLS, username = server SMTP username (server ID), password = server SMTP password/injection API key. Free trial and setup.
SocketLabs outgoing mail server:
smtp.socketlabs.com, port <code>587</code> (STARTTLS) or <code>2525</code> (STARTTLS) or <code>25</code> (STARTTLS), username = the server's SMTP username (Injection → SMTP Credentials), password = the server's SMTP password.
SocketLabs SMTP settings at a glance
| Outgoing (SMTP) host | smtp.socketlabs.com |
|---|---|
| Ports & encryption |
587 — STARTTLS <em>(recommended)</em>2525 — STARTTLS25 — STARTTLS |
| Username | the server's SMTP username (Injection → SMTP Credentials) |
| Password | the server's SMTP password |
| Authentication | Each SocketLabs "server" has its own injection credentials; Hurricane Server, Email Delivery Server and On-Demand tiers differ in limits. |
How to set up SocketLabs SMTP
- Servers → your server → Injection → SMTP Credentials.
- App settings: host smtp.socketlabs.com, port 587, STARTTLS, username/password from the server.
Sending limits
- Free trial around 500 emails per month, then plans from about $40/month.
- Sending domain must be validated (DKIM, SPF, custom bounce domain).
Things that catch people out
- Port 465 is not offered.
Common SocketLabs SMTP errors
| Server reply | Meaning | Fix |
|---|---|---|
535 Authentication failed | Wrong server credentials. | Copy from the server's Injection page. |
More codes: 535 authentication failed, 550 relay denied, 554 rejected as spam, connection timed out — or all SMTP error codes.
When SocketLabs is not enough for your app
When a provider caps you or blocks a port, point the same app at QueenSMTP instead: host smtp.queensmtp.com, port 587 (STARTTLS) or 465 (SSL), your SMTP username and password from the dashboard. $5/year plus $0.10 per 1,000 emails, 100 free a day to test.
Get SMTP credentials — free to test Test SocketLabs nowRelated settings
SocketLabs SMTP — questions
smtp.socketlabs.com on port 587, 2525 or 25 with STARTTLS, using the server's SMTP username and password.
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