Is Microsoft Word encrypted?
Only if you turn on password encryption, one document at a time, in Word on Windows or Mac. Otherwise Microsoft can read the documents you save to OneDrive. A locked document can't be opened in a browser or edited together with others.
Checked on 25 October 2026 against 8 sources.
Made by Secria, which is building Secria Workspace. We grade every app by the same rules. How we check
- Your notes and docsOnly you, once you turn it onEach document needs its own password, set in Word on Windows or Mac, and a locked one can't be opened in a browser or edited together with others; without a password, Microsoft holds the keys to documents in OneDrive.1, 2, 3, 4Turn it on
- Shared with othersMicrosoft can read itEditing together doesn't work with a password-locked document, so documents you share for co-editing are open to Microsoft.3, 4
- Post-quantumNot yetNo post-quantum protection for stored documents announced as of 25 October 2026; Microsoft says it aims to move its products to it by 2029.7
- Who holds the keys
- Microsoft holds the keys to documents in OneDrive, but only your password opens a password-locked document.
- What Microsoft can still see
- Documents you save to OneDrive, which Microsoft indexes for search, and the content you send to connected features such as Editor or translation.
On business plans, admins with Microsoft 365 E5 can set up Double Key Encryption, so Microsoft can't open labelled documents.
Lock a document with a password
- Open the document in Word on Windows or Mac. Word for the web can't do this.
- On Windows, select File › Info › Protect Document › Encrypt with Password. On a Mac, select Review › Protect › Protect Document.
- Type a password to open the document, type it again to confirm, then save.
Takes a minute for each document. Word can't recover a lost password, so keep it somewhere safe. A locked document can't be opened in a browser or edited together with others.
Email is worth checking next: Gmail, Outlook and iCloud Mail can all read your mailbox. See which email services can.
Can Microsoft read my Word documents?
If they're saved to OneDrive, yes. Microsoft says each file is encrypted at rest with its own key, and it keeps the master keys that protect those keys4, 8. Its privacy statement says it indexes your OneDrive documents so you can search them, and that some Word features use your document's content to make suggestions5.
On some business plans, admins can add Double Key Encryption, which Microsoft says keeps labelled documents out of reach of its online services, including Copilot6.
How do I password protect a Word document?
In Word for Windows, select File › Info › Protect Document › Encrypt with Password. On a Mac, use Review › Protect › Protect Document and set a password to open it1. Word for the web can't add a password1.
Microsoft says Word can't recover a lost document password1. Word for the web can't open documents encrypted with a password, so you open them in the desktop app2. Only a password to open locks the document: one that only stops changes still lets it open for reading in a browser2.
Can I share a password-protected Word document?
You can send it, and anyone with the password can open it in the Word desktop app2. But editing together doesn't work on password-protected documents3. To edit with others, you'd have to remove the password, and then Microsoft can read the document again4.
How Microsoft Word compares
Sorted by how many parts are sealed by default, then by how many can be. Ties go A to Z.
Sources
- Protect a Word document with a password (Microsoft Support), Microsoft. Read on 25 Oct 2026.
- Differences between using a document in the browser and in Word (Microsoft Support), Microsoft. Read on 25 Oct 2026.
- Troubleshoot co-authoring Word documents (Microsoft Support), Microsoft. Read on 25 Oct 2026.
- How OneDrive safeguards your data in the cloud (Microsoft Support), Microsoft. Read on 25 Oct 2026.
- Microsoft Privacy Statement (updated September 2026), Microsoft. Read on 25 Oct 2026.
- Double Key Encryption (DKE) (Microsoft Learn), Microsoft. Read on 25 Oct 2026.
- Accelerating the quantum-safe timeline (Microsoft Security Blog, 30 June 2026), Microsoft. Read on 25 Oct 2026.
- Encryption in Microsoft 365 (Microsoft Learn), Microsoft. Read on 25 Oct 2026.
Changes to this answer
- First published.