For an AI agent that works in Outlook mail, Fluxmail is the best fit for most people. It has dedicated email tools, connects Microsoft 365, Exchange, and Outlook alongside Gmail and IMAP, and runs hosted or on your own machine, with self-hosted support for personal Outlook.com and Hotmail accounts. If your organization is on Microsoft 365 and the agent also needs calendar, Teams, and SharePoint, use Microsoft's Work IQ MCP or Claude's Microsoft 365 connector. Both need a work account and a tenant administrator. The best free open-source option is ms-365-mcp-server.
Product details come from each vendor's docs and pricing pages as of October 23, 2026. We make Fluxmail, so it's listed first. For Gmail and IMAP as well as Outlook, see The best email MCP servers for AI agents.
What should I look for in an Outlook MCP server?
Outlook has more setup variations than Gmail, so start with your account type:
- Personal Outlook.com, Hotmail, and Live addresses don't work with Claude's Microsoft 365 connector or Zapier, and Microsoft doesn't document them for Work IQ.
- With a Microsoft 365 work or school account, an Entra administrator approves a server's permissions if your tenant blocks user consent, and Work IQ and Claude's connector need a Global Administrator to enable them for the tenant.
- On-premises Exchange without Microsoft Graph needs a server that speaks IMAP and SMTP.
Then check whether the agent can send without an administrator changing tenant policy, whether it can read attachments, and whether you can limit each agent to certain mailboxes and actions.
What are the best Outlook MCP servers?
1. Fluxmail
Fluxmail gives agents one set of email tools across Microsoft 365, Outlook, Exchange, Gmail, and IMAP. The tools search mail, read threads, draft, send, reply, forward, and download attachments, and they can move messages between folders, archive them, or move them to trash. Replies fill in recipients, subject, and threading from the original message, and forwards carry over its subject, content, and attachments to the recipients the agent chooses, so the agent doesn't have to build Microsoft Graph requests. Fluxmail handles email only, with no calendar or Teams tools.
Fluxmail Cloud hosts the server at https://cloud.fluxmail.ai/mcp. You connect Outlook by signing in with Microsoft in the dashboard, and a work tenant may require administrator consent. Each MCP client then signs in to Fluxmail with OAuth, and you choose its mailboxes and permission level: Read only, Read and write, or Full mail access with sending. Cloud doesn't store messages, and it also has a REST API.
Self-hosted Fluxmail runs on your computer or in Docker and keeps Microsoft tokens on your machine. You register your own Entra app, and if the app allows personal accounts, it connects Outlook.com and Hotmail as well as Microsoft 365. Self-hosted also has a CLI and scheduled sending. On-premises Exchange connects over IMAP and SMTP. See Connect an Outlook account and Connect on-premises Exchange to an AI agent.
Self-hosted is free for one member and three mailboxes. Pro is $15 a month for ten mailboxes and Business is $25 per member a month. Cloud starts with a seven-day trial.
2. Claude's Microsoft 365 connector
Claude's Microsoft 365 connector is available on every Claude plan, from Free to Enterprise. It searches Outlook mail, including archived mail and shared mailboxes you can access, along with SharePoint, OneDrive, and Teams. Access is read-only until an administrator turns on write actions. After that, Claude can send mail, manage drafts, and create calendar events, but it can't attach files to drafts or sends.
The connector needs a work or school account on a Microsoft Entra tenant, so personal Outlook.com and Hotmail accounts can't connect, and a Global Administrator must grant consent once. It only works inside Claude.
ChatGPT has its own Outlook Email app that searches and references messages in a connected account. It only works inside ChatGPT, and for work accounts an Entra administrator may need to approve its permissions.
3. Microsoft Work IQ MCP
Work IQ MCP is Microsoft's hosted MCP server for Microsoft 365, usable from any MCP client. It has 12 generic tools that operate on Microsoft Graph paths, so reading mail is fetch /me/messages and sending is do_action /me/sendMail. The same tools reach calendar, files, Teams, and people, and an ask tool calls Microsoft 365 Copilot.
A Global Administrator enables it for the tenant. Create, update, delete, and send requests are blocked by default until an administrator allows them, and that policy covers the whole tenant rather than a single app or agent. Results return 25 items by default and 100 at most. Usage is billed in Copilot Credits through an Azure subscription. See Fluxmail vs Work IQ MCP.
4. ms-365-mcp-server
ms-365-mcp-server is an open-source server from Softeria (MIT, about 1,100 GitHub stars) with over 300 tools across Outlook mail, calendar, OneDrive, Excel, and more. Its mail tools read, send, reply, forward, and handle attachments.
Personal Microsoft accounts work by default, and org mode turns on work features such as shared mailboxes and Teams. The server ships with a built-in app registration, or you can bring your own. A --read-only flag, presets, and regex tool filters limit what the agent sees. It runs locally with device-code sign-in, or over HTTP with OAuth.
5. Composio Outlook
Composio's Outlook toolkit has 328 tools covering mail, calendar, and contacts, plus event triggers. Composio can manage OAuth through its own Microsoft app or use yours, and gives each user a hosted MCP URL. It suits products whose users connect their own Outlook accounts, or agents that use Outlook alongside many other apps. Its documented setup focuses on work accounts.
If you use your own OAuth app, the free Hobby plan has 100,000 tool calls a month. Pro is $29 a month, which covers the first $29 of usage, and each call after that costs $0.0003 with your own OAuth app or $0.0005 with Composio's managed apps.
6. Zapier MCP
Zapier MCP exposes Zapier's Microsoft Outlook actions as MCP tools. Each successful call costs two tasks from your Zapier plan. The free plan's 100 tasks cover about 50 calls a month, and Pro starts at $19.99 a month billed annually for 750 tasks. Zapier's Outlook integration only connects Microsoft 365 business and enterprise accounts, not Outlook.com. It makes the most sense if your Outlook workflows already run through Zapier.
How do they compare?
| Server | Personal Outlook.com | Admin needed for work accounts | Sends | Calendar and Teams | Price |
|---|---|---|---|---|---|
| Fluxmail | Self-hosted | Consent, if your tenant requires it | Yes | No | Free self-hosted plan; Pro $15 a month |
| Claude Microsoft 365 connector | No | Global Admin consent; admin enables writes | After an admin enables it | Yes | Included in Claude plans |
| Work IQ MCP | Not documented | Global Admin enables; admin allows writes | After an admin allows it | Yes | Copilot Credits |
| ms-365-mcp-server | Yes | Consent, if your tenant requires it | Yes | Yes | Free |
| Composio Outlook | Not documented | Consent, if your tenant requires it | Yes | Yes | Free tier; Pro $29 a month plus usage |
| Zapier MCP | No | Consent, if your tenant requires it | Yes | Yes | 2 tasks per call |
Frequently asked questions
Is there an official Microsoft Outlook MCP server?
Yes. Microsoft's Work IQ MCP covers Outlook mail along with the rest of Microsoft 365. It needs a Microsoft 365 tenant, a Global Administrator to enable it, and usage-based billing. Sending stays blocked until an administrator allows it.
Can I connect a personal Outlook.com or Hotmail account to Claude?
Not with Claude's Microsoft 365 connector, which only accepts work and school accounts. Self-hosted Fluxmail and ms-365-mcp-server both connect personal Microsoft accounts. Triage your Outlook inbox with Claude Code walks through it with Fluxmail.
Do I need my Microsoft 365 admin to approve an Outlook MCP server?
Often. Many tenants block users from consenting to third-party apps, so an administrator approves the app's permissions once. Work IQ and Claude's Microsoft 365 connector also need a Global Administrator to enable them, and another admin step before they can send.
Can an Outlook MCP server work with on-premises Exchange?
Only over IMAP and SMTP, since the Graph-based servers above need Exchange Online. Fluxmail connects Exchange servers over IMAP and SMTP. In Cloud, the server needs a public hostname and a valid TLS certificate. See Connect on-premises Exchange to an AI agent.
Which one can download Outlook attachments?
Fluxmail has a dedicated download_attachment tool that returns the file to the agent, and ms-365-mcp-server and Composio have attachment tools. Work IQ has a generic binary fetch tool with a 4 MB default limit, but Microsoft doesn't document using it for mail attachments.