Issue Description

Some users have reported that the default font in Microsoft Outlook has unexpectedly changed from Calibri to a different font (e.g., Aptos). This change affects new emails, replies, and calendar invites.

Cause

Microsoft has recently updated the default font across Microsoft 365 applications, including Outlook. The new default font is Aptos, replacing Calibri as part of a broader design refresh. This change may have been applied automatically through a Microsoft 365 update.

Resolution: Restore Calibri as the Default Font

If you prefer to continue using Calibri, follow the steps below to manually reset it as your default font.

For Outlook Desktop App (Windows/Mac)

Depending on your version of Outlook, you may either follow the steps below or use the same instructions as for Outlook on the Web (see next section).

1. Open Outlook.
2. Go to File > Options.
3. Select Mail > Stationery and Fonts.
4. Under each section ("New mail messages", "Replying or forwarding messages", and "Composing and reading plain text messages"), click Font.
5. Choose Calibri, set your preferred size and style, then click OK.
6. Click OK again to save your changes.

For Outlook on the Web (OWA)

1. Click the Settings gear in the top-right corner.
2. Select Mail > Compose and reply.
3. Under "Message format", choose Calibri from the font dropdown.
4. Click Save.

Need Additional Support?

This guide aims to provide useful information, but as technology changes, interfaces or steps might vary. Please use the Comment button to let us know if anything differs from your experience. Your feedback helps us keep this information accurate. Thank you!