How to Use Claude for Outlook (Add-in Setup and Best Prompts)

If your workday lives in Outlook, Claude for Outlook brings Anthropic's AI assistant straight into your inbox and calendar. It can triage unread mail, draft replies in your voice, summarize long threads with citations and prepare you for meetings, without ever sending anything on its own. Here's how to set it up and use it well.

What Claude for Outlook can do

According to Anthropic's help center, you can:

• Triage your unread inbox into what needs you, what Claude can handle, and what is noise.
• Draft replies, reply-alls and forwards in your voice, placed unsent in Outlook's compose pane.
• Summarize long threads into decisions, open items and who owes what, with per-email citations.
• Read .docx and .xlsx attachments inline.
• Find meeting times and draft invites in Outlook's appointment form.
• Prep for meetings with a one-page brief of recent threads and attachments.
• Search your mailbox by topic, with citations that open the original email.

Requirements

How to install it (individual users)

1. Go to the Claude for Outlook listing on Microsoft AppSource (linked from Anthropic's help center).
2. Select Get it now.
3. Open Outlook and open any email.
4. Select the Claude button in the message ribbon and sign in with your Claude account.

For admins: organization deployment

Admins can deploy via the Microsoft 365 Admin Center (Integrated apps), or upload a manifest file if the Office Store is blocked. Claude for Outlook reads mail and calendar data through Microsoft Graph, which requires a one-time tenant-wide consent from a Global Administrator. Otherwise users see a "Need admin approval" message. Anthropic documents the permissions requested: Mail.ReadWrite, Calendars.Read, User.Read and offline_access, and an option to use your own Entra app registration.

Best prompts for daily use

Inbox triage

What needs me today?

Draft replies for everything you can handle.

Archive all the calendar responses and newsletters.

Claude sorts unread mail into action items (each with a one-line reason), items it can handle (pre-drafted for your review) and noise.

Replies

Reply to this, agree to the new deadline and ask for the final file by Thursday.

Forward this to Sara with a two-line summary.

Anthropic says Claude learns tone from your sent folder, leaves the closing off so your Outlook signature isn't duplicated, chooses reply vs. reply-all deliberately, and warns before adding anyone who wasn't on the thread.

Long threads

What's been decided and what's still open?

Who owes what on this thread?

Attachments, search and calendar

Summarize the attached document.

Find the email where the supplier sent the revised price list.

Find 30 minutes with Omar and the design team next week.

Prep me for my 2 PM meeting.

Working across Office apps

Claude for Outlook shares context with Claude for Excel, PowerPoint and Word. For example, you can open an attached document in Word with the email thread already loaded as context, or pull numbers from an email into a spreadsheet. See how to use Claude for Excel.

Privacy: how Claude accesses your mailbox

• Claude reads the open email via Office.js and uses Microsoft Graph for mailbox-wide tasks. Anthropic says the Graph token stays in your browser and is never sent to Anthropic.
• When signed in with a Claude account, mailbox content Claude reads becomes part of the prompt sent to Anthropic's API, and the add-in doesn't keep a server-side copy or index of your mailbox.
• Chat history is stored locally in your browser and not synced across devices.
• For Claude for Outlook use, Anthropic says inputs and outputs are deleted from its backend within 30 days, with documented exceptions.

Safety: watch out for prompt injection

Anthropic explicitly warns that email bodies and attachments are untrusted input. A malicious email could hide instructions trying to make the AI forward a thread or draft something you didn't ask for. Protect yourself:

• Review every draft and action before accepting, especially recipient lists.
• Be extra careful with emails from external or unknown senders.
• Verify summaries against cited emails for high-stakes conversations.
• Don't use it for privileged or regulated data without proper organizational controls.

Claude for Outlook vs. Gemini in Gmail

If you use Gmail instead, Google's Gemini features (summaries, Help me write, AI search) cover similar ground. See how to use Gemini to clean up Gmail. Choose based on where your email lives.

A daily 15-minute Outlook routine with Claude

1. Morning triage (5 min): ask Claude to list the emails that need a reply today, grouped by urgency, with one line each on what's being asked.
2. Draft replies (5 min): for each important email, ask for a short draft in your tone, then edit and send it yourself. Claude only drafts; you stay in control of every message that leaves your mailbox.
3. Calendar check (2 min): ask what meetings you have today and whether any email threads relate to them.
4. End of day (3 min): ask for a list of open questions you're waiting on from others.

Using Excel heavily as well? Read how to use Claude for Excel. Managing a whole project from your inbox? See Claude for project management.

Summary

Claude for Outlook turns your inbox into a manageable to-do list: triage unread mail, draft replies in your voice, summarize threads with citations, read Word and Excel attachments, schedule meetings and prepare briefs. It requires a paid Claude plan and Exchange Online. It never sends anything without you. Review every draft, stay alert to prompt injection, and you'll save hours every week.

Frequently asked questions