Connect IONOS to Claude,
and Cursor, ChatGPT, any MCP client
Give your AI agent a real IONOS inbox in minutes. Read, search, send, reply, schedule and organize mail with IMAP and your mailbox password, and use the same inbox in every MCP client, not just one.
Claude cannot reach IONOS on its own. mcpemails is a hosted MCP server that connects it over IMAP using your mailbox password, so Claude, Cursor or any MCP client can read, search, send and organize that mail. Setup takes a couple of minutes and one inbox is free.
How IONOS connects: IMAP and your mailbox password
IONOS connects over IMAP/SMTP with the email password you set in the IONOS control panel under Email, which is separate from your IONOS login. IONOS answers on both standard transports, 993 with TLS and 143 with STARTTLS, and guessing between them is the most common way an IONOS connection fails. mcpemails fills in a working pair and retries the other if the first does not answer, so a rejected login here really is the password.
The exact IONOS IMAP and SMTP settings
Copy these into the connect form. mcpemails prefills them where it can, and retries the other standard transport if the first does not answer.
| Protocol | Server | Port | Security |
|---|---|---|---|
| IMAP (incoming) | imap.ionos.com | 993 | TLS (implicit) |
| SMTP (outgoing) | smtp.ionos.com | 465 | TLS (implicit) |
Verified 2026-08-31: imap.ionos.com answered a TLS connection and identified itself as an IMAP server under that name. It advertises LOGIN, PLAIN authentication.
Sign in with: The full email address, for example john.doe@example.com. IONOS gives every address its own password.
A IONOS inbox your agent can actually use
Nine action-based MCP tools, not just drafts. Your agent finishes the job inside IONOS.
- 01Read
Read & search mail
List, read and search across folders to find that invoice, summarize a thread, or pull the latest from a sender.
- 02Send
Send, reply & forward
Compose and send real messages, reply in-thread, and forward, directly from your mailbox, not as a draft you finish by hand.
- 03Schedule
Schedule for later
Queue a message to go out at the right time, so your agent can draft now and send on schedule.
- 04Organize
Move, copy, flag, archive, delete
Keep the inbox tidy: file mail into folders, flag what matters, archive the rest, or delete on request.
Connect IONOS in four steps
From sign-up to first AI email in a couple of minutes.
Create a free account
Sign up for mcpemails, no card required. The free plan connects one inbox, forever.
Get your IONOS mailbox password
In the IONOS control panel, open Email, pick the address and set or reset its password. It is not the password you use to sign in to IONOS itself.
Paste it into mcpemails
Choose IMAP / SMTP, add your IONOS address, the hosts below and the password to connect the inbox securely.
Paste the MCP URL into your AI
Drop https://mcpemails.com/api/mcp into Claude, Cursor or ChatGPT, authorize, and your agent has the inbox.
Comparing providers first? See the email provider compatibility matrix
What actually goes wrong with IONOS
On IONOS the port is almost never the cause, and cycling ports wastes days
This is the most useful thing we can tell you about IONOS, and it comes out of our own connection logs rather than any manual. One workspace made twelve consecutive failed attempts against imap.ionos.com, alternating between 993 with implicit TLS and 143 with STARTTLS on the assumption that one of the two transports was wrong. IONOS answers on both. The password was the problem the entire time. IONOS documents 993 for IMAP and 465 for SMTP, and offers 587 with STARTTLS as an outgoing alternative for networks that block 465, so the transport is genuinely flexible and genuinely not what refuses your login. If the server answers and then rejects you, treat it as a credential problem and go straight to the control panel.
Every IONOS address carries its own password, and it is not your IONOS login
IONOS states plainly that each email address has its own password. The credential you use to sign in to IONOS itself, which is very often an email address too, authenticates the control panel and nothing else. Set or reset the mailbox password in the IONOS control panel under Email, by selecting the address and using the password option on it. Because both credentials look identical in a login form, this is the single most common IONOS connection failure, and it is exactly the failure the port-cycling above was mistaken for.
Microsoft 365 sold by IONOS is a Microsoft mailbox, not an IONOS one
IONOS resells Microsoft 365 alongside its own Mail Basic and Mail Business products, and a large number of customers who think they have IONOS email actually have a Microsoft tenant with an IONOS invoice. Nothing on imap.ionos.com applies to those mailboxes: they live on Microsoft's servers and are administered from the Microsoft 365 Admin Center rather than the IONOS control panel. Microsoft's default tenant policy blocks an ordinary end user from consenting to third-party mail read and write access, which is set by Microsoft and by your tenant administrator. We do not claim to connect them. The tell is where your webmail takes you: Outlook on the web means Microsoft.
Every IONOS country brand, and every legacy 1&1 address, uses the same two hosts
IONOS runs separate storefronts on ionos.de, ionos.co.uk, ionos.fr, ionos.es, ionos.it and ionos.com, and those exist for billing and marketing rather than because the mail platform is regional. IMAP is imap.ionos.com and SMTP is smtp.ionos.com whatever storefront sold you the mailbox. Third-party guides that still insist on region-specific names built from the old 1&1 brand pre-date the rebrand, and following them puts you on a hostname that does not answer. There is no regional host to hunt for.
Known limits with IONOS
- Microsoft 365 mailboxes bought through IONOS cannot be connected. Microsoft's default tenant policy blocks end-user consent for third-party mail access.
- mcpemails connects a mailbox. IONOS aliases, forwarders, catch-all rules and spam settings stay in the IONOS control panel and are not visible to your AI client.
IONOS and AI: common questions
Does Claude work with IONOS email?
It works with an IONOS mailbox, the kind served by imap.ionos.com, once an MCP server such as mcpemails is connected to it over IMAP. Claude has no built-in IONOS connector. It does not work with a Microsoft 365 mailbox bought through IONOS, because Microsoft's default tenant policy blocks third-party mail access consent.
What are the IONOS IMAP and SMTP settings?
IMAP is imap.ionos.com on port 993 with SSL/TLS and SMTP is smtp.ionos.com on port 465, also SSL/TLS. IONOS documents port 587 with STARTTLS as an outgoing alternative if your network blocks 465. The username is your complete email address. Both hosts were confirmed from a live TLS connection on the date shown on this page.
Should I use IONOS port 993 or 143?
Use 993 with implicit TLS, which is what IONOS documents. The reason this question comes up so often is that clients propose 143 automatically and IONOS answers there too, so people conclude the port is the variable when a login is refused. It is not. If the server answers and rejects the credentials, the password is what is wrong.
Why is my IONOS email password rejected?
Because IONOS gives every email address its own password and you are probably using your IONOS account login instead. Open the IONOS control panel, go to Email, select the address and set a new password for it, then use that. If the address was migrated to Microsoft 365, it no longer exists on the IONOS mail servers at all.
Do IONOS UK, German and French accounts use different servers?
No. The regional IONOS storefronts share one mail platform, and every mailbox uses imap.ionos.com and smtp.ionos.com regardless of which country site sold it. Guides showing region-specific hostnames built from the old 1&1 brand are out of date and those names will not connect.
Is my IONOS mail stored on your servers?
No. Messages are fetched live from IONOS over IMAP for each request and handed to your AI client. Credentials are encrypted at rest and message bodies are not retained.
Give your AI an IONOS inbox
Connect IONOS in minutes. One inbox free forever, no card required.