Microsoft 365 Copilot: Custom dictionary expands language support and increases limits for Teams meeting transcripts
Microsoft 365 Copilot’s custom dictionary now supports more languages, doubles per-language entry limits to 1,000, and allows incremental CSV uploads for easier management. These updates improve Teams meeting transcript accuracy and will roll out globally by late January 2026, enabling enhanced Copilot and Intelligent Recap features automatically.

We’re enhancing the custom dictionary feature in Copilot Settings to add support for more languages, increase per‑language dictionary limits, and streamline dictionary management. These improvements help organizations improve transcript accuracy for Microsoft Teams meetings and support better Copilot and Intelligent Recap experiences. This update also aligns with customer feedback requesting broader language coverage and easier ongoing dictionary maintenance.
A Microsoft 365 Copilot license is required for the meeting organizer or transcription initiator to apply transcript enhancements that rely on custom dictionary entries.
This update applies to Teams meeting transcripts on Teams for Windows, Teams for Mac, Teams for the web, and Teams for iOS and Android.
When this will happen
General Availability (Worldwide): Rollout began in mid-January 2026 and is expected to complete by late January 2026.
How this affects your organization
Who is affected:
- Organizations that use Teams meeting transcripts.
- Admins who manage custom dictionary entries in Copilot Settings.
- Users relying on Copilot or Intelligent Recap features during or after meetings.
What will happen:
- Expanded language support: The custom dictionary will support Chinese (Traditional), Dutch, Korean, Thai, and Turkish, in addition to the currently supported Chinese (Simplified), English, French, German, Italian, Japanese, Portuguese, and Spanish.

- Increased entry limits: Per-language maximum increases from 500 to 1,000 entries.

- Simplified dictionary management: Admins can upload incremental CSV files to append new terms.

- This feature will be enabled automatically when rollout completes.
What you can do to prepare
No action is required before rollout.
- Notify admins or user groups about the new capabilities.
- Review current dictionaries and consider using the expanded entry limit.
- Determine whether your organization will use newly supported languages.
- Use the new Add entries upload option to update dictionaries incrementally.
- Update internal documentation as needed.
Learn more: Manage custom dictionaries for Microsoft Teams meetings and events | Microsoft Teams | Microsoft Learn
Compliance considerations
No compliance considerations identified. Review as appropriate for your organization.
Message ID: MC1221925

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