mailintel
I
hostingionos

IONOS Mail IMAP and SMTP settings

IONOS (formerly 1&1) hosts mail in Europe and the US. The default endpoints are imap.ionos.com and smtp.ionos.com.

Connection
IMAP host
imap.ionos.com

port 993 · SSL/TLS

SMTP host
smtp.ionos.com

port 465 · SSL/TLS

Username

your full email address
password: mailbox password
Setup

Connect in three steps

  1. 1

    Use the full address as the username.

  2. 2

    If you're on a US contract, the hosts may be `imap.ionos.com` and `smtp.ionos.com` as well — check the control panel.

Watch out

What usually breaks

  • IONOS has separate Mail Basic and Mail Business products with different limits.

  • Accounts migrated from 1&1 may still use legacy hostnames.

Detect it

Resolve it instead of hardcoding it

A custom domain on IONOS Mail has the same MX infrastructure as the consumer product. That is what mailintel reads.

ionos.ts
import { mailintel } from "mailintel";

const result = await mailintel("[email protected]");

result.provider;              // "ionos"
result.connection.imap;       // { host: "imap.ionos.com", port: 993, security: "tls" }
result.connection.smtp;       // { host: "smtp.ionos.com", port: 465, security: "tls" }
result.connection.username;   // "[email protected]"
FAQ
What is IONOS Mail's IMAP server?+

imap.ionos.com on port 993 using SSL/TLS. The username is the full email address.

What is IONOS Mail's SMTP server?+

smtp.ionos.com on port 465 using SSL/TLS. Most clients also accept the alternate submission port with STARTTLS.

Does IONOS Mail need an app password?+

Not necessarily — a regular mailbox password works, though a dedicated app password is still a good idea if the provider offers one.