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IONOS email IMAP, POP3 and SMTP settings
These are the settings IONOS publishes on its US help pages for its hosted mailboxes, checked on November 1, 2026. IONOS also runs country sites with their own host names, so match the help page to the IONOS site you signed up on.
Founder of Shipmail, the email platform for businesses and their AI agents. Every guide here draws on mail servers running in production.
- IONOS
- IMAP
- SMTP
- POP3
Short answer
For IONOS Mail Basic and Mail Business, the IMAP server is imap.ionos.com on port 993 with SSL/TLS, and the SMTP server is smtp.ionos.com on port 465 with SSL/TLS. POP3 is pop.ionos.com on port 995. If port 465 is blocked, use port 587 with STARTTLS. Sign in with your full email address and the password of that address, not your IONOS account login.
IONOS mail server settings
IONOS IMAP, POP3 and SMTP servers
These values apply to IONOS Mail Basic and IONOS Mail Business. IONOS recommends IMAP over POP3.[1]
- Incoming (IMAP):
imap.ionos.com, port993, SSL/TLS - Incoming (POP3):
pop.ionos.com, port995, SSL/TLS - Outgoing (SMTP):
smtp.ionos.com, port465, SSL/TLS - Username: the full email address, such as
john.doe@example.com - Password: the password set for that email address. Each address has its own.
To check a password before blaming the app, sign in to IONOS Webmail with the same address and password. Hosted Microsoft Exchange from IONOS is a different product with its own setup article; these servers do not apply to it.[1]
Country sites use their own host names
The IONOS UK help page lists imap.ionos.co.uk, pop.ionos.co.uk and smtp.ionos.co.uk, on the same ports. If you bought your mailbox on a country site, use the host names from that site's help page.Sources[2]IONOS UK Help: mail server details for IMAP, POP3 and SMTP[1]IONOS Help: mail server details for IMAP, POP3 and SMTP
When port 465 is blocked: use 587
Sender address rule and sending limits
IONOS also limits how many emails a Mail Basic or Mail Business account sends per hour, and the limit grows with the account's age:[3]
- Up to 7 days old: 50 emails per hour
- 8 to 14 days: 100 emails per hour
- 15 to 30 days: 400 emails per hour
- Older than 30 days: 500 emails per hour
Over the limit, the app shows a server error ending in 450 Mail send limit exceeded. Wait for the hour to pass, or send newsletters through a newsletter tool rather than a mailbox.[3]
Common IONOS email problems
- Password rejected: you used the IONOS account login. Use the password of the email address itself, and test it in Webmail.
- Sending fails with correct settings: port 465 may be blocked on your network. Switch to 587 with STARTTLS.
- Message rejected when sending from an alias: the From address is on another domain. Only addresses on the mailbox's domain are accepted.
450 Mail send limit exceeded: the hourly limit for the account's age was reached.- Settings do not match a co.uk or other country address: use the host names from that country's IONOS help page.
If you also need to change the domain's records at IONOS, our IONOS custom domain email guide covers that side.
Using a mailbox on your own domain instead
An IONOS mailbox is tied to an IONOS mail plan, but the address is on your domain, so it can move. Point the domain's MX records at the new host, then import the mail while the IONOS plan is still active.
A Shipmail mailbox on your own domain works in the same apps with one set of settings: server mx1.shipmail.to, IMAP on port 993 with SSL/TLS, SMTP on port 465 with SSL/TLS or 587 with STARTTLS, and your full address as the username. Plans start at $4 a month for 2 mailboxes. It is not free, and it only makes sense if you want an address you own rather than one tied to a provider.Sources[4]Shipmail email client connection settings[5]Shipmail pricing
Sources5 sourcesVerified 2026-11-01
- [1]IONOS Help: mail server details for IMAP, POP3 and SMTP
For IONOS Mail Basic and Mail Business: IMAP `imap.ionos.com` port 993 SSL/TLS (recommended), POP3 `pop.ionos.com` port 995 SSL/TLS, SMTP `smtp.ionos.com` port 465 SSL/TLS. Username is the full email address; the password is the one set for that address, each address has its own. If port 465 is blocked, use 587 with STARTTLS (TLS in Outlook 2016/2019). Since January 29, 2024 the SMTP server accepts a different sender address only if it uses the same sender domain, and rejects other emails. Hosted Microsoft Exchange has a separate setup article.
ionos.com · 2026-11-01
- [2]IONOS UK Help: mail server details for IMAP, POP3 and SMTP
The UK help page lists `imap.ionos.co.uk` port 993, `pop.ionos.co.uk` port 995 and `smtp.ionos.co.uk` port 465, all SSL/TLS, with port 587 and STARTTLS as the alternative when 465 is blocked.
ionos.co.uk · 2026-11-01
- [3]IONOS Help: restrictions on sending bulk emails
For Mail Basic and Mail Business, the hourly sending maximum depends on account age: 50 emails per hour up to 7 days, 100 for 8 to 14 days, 400 for 15 to 30 days, 500 after 30 days. Over the limit the server answers `450 Mail send limit exceeded`.
ionos.com · 2026-11-01
- [4]Shipmail email client connection settings
Shipmail IMAP, SMTP, and JMAP settings: mx1.shipmail.to, IMAP on port 993 with SSL/TLS, SMTP on port 465 with SSL/TLS or 587 with STARTTLS, the full email address as username, and the mailbox password or an app password.
shipmail.to · 2026-10-15
- [5]Shipmail pricing
Shipmail plan prices, mailbox limits, team access, and send limits.
shipmail.to · 2026-10-15
Questions worth answering
Common questions about ionos email settings.
What is the IONOS IMAP server?
imap.ionos.com on port 993 with SSL/TLS, for Mail Basic and Mail Business.[1]What is the IONOS SMTP server?
smtp.ionos.com on port 465 with SSL/TLS. If 465 is blocked, use port 587 with STARTTLS.[1]What username and password does IONOS email use?
How many emails can I send with IONOS?
Why does IONOS reject mail from my alias?
Related guides
More on Shipmail pricing, comparisons, and team workflows.
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