MC1466753 – M365 Change Digest

One-line summary

Microsoft is retiring the Similarity Checker feature in Word as of October 3, 2026. After this date, the feature will no longer be available in Microsoft Editor for Word.

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Details

Summary

Microsoft Word's Similarity Checker will be retired on October 3, 2026, and removed from Microsoft Editor. Other writing and editing features, including Microsoft 365 Copilot, remain unaffected. Organizations should review workflows, inform users, and consider alternatives if needed. No action or compliance issues are required.

Body (from Message Center)

[What and why]

We are retiring Similarity Checker in Microsoft Word on October 3, 2026. After the retirement date, Similarity Checker will no longer be available as part of the Microsoft Editor experience in Word.

This change allows us to focus on experiences and capabilities that are more broadly used across Microsoft Word.

[Rollout schedule]

Worldwide, GCC, and DoD: Beginning on October 3, 2026

[Impact on your organization]

Who is affected

Organizations and users that currently use Similarity Checker in Microsoft Word

Platforms and services

Microsoft Word
Microsoft Editor

What will happen

Similarity Checker will be removed from Microsoft Word.
After retirement, users will no longer be able to access Similarity Checker through the Editor experience in Word.
Other Microsoft Word writing, editing, and citation capabilities will not be affected.
Microsoft Editor will continue to provide spelling, grammar, clarity, and style suggestions.
Microsoft 365 Copilot capabilities in Word are not affected by this change.
Note: Copilot is not intended to serve as a formal similarity, plagiarism, or originality validation tool.

[Action required and recommendations]

No action is required.

If your organization currently uses Similarity Checker:

Review workflows that depend on Similarity Checker.
Inform users who rely on the feature about the upcoming retirement.
Evaluate alternative solutions if formal similarity or originality validation is required.
Update internal documentation or training materials that reference Similarity Checker.

[Compliance considerations]

No compliance considerations identified. Review as appropriate for your organization.

Raw JSON (for debugging)

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      "Summary": "Microsoft Word\u0027s Similarity Checker will be retired on October 3, 2026, and removed from Microsoft Editor. Other writing and editing features, including Microsoft 365 Copilot, remain unaffected. Organizations should review workflows, inform users, and consider alternatives if needed. No action or compliance issues are required."
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