What a default font does, and why you might want to change it

A default font is the typeface Outlook uses automatically every time you start typing a new email. By default, Outlook ships with Calibri or Aptos (depending on your version), but you can change it to any font installed on your computer. This matters because the font you choose affects how your emails look to the person reading them — and it stays consistent across every message you send, so you do not have to pick a font each time.

You might want to change your default font if Calibri looks too casual for work emails, if you prefer a serif font like Times New Roman for readability, or if your workplace has a style guide that specifies a particular typeface. Once you set it, Outlook remembers your choice and applies it to every new message until you change it again.

Key Takeaways

  • Your default font is the typeface Outlook uses automatically when you compose a new email, and you can change it to any font installed on your computer.
  • The steps to change your default font differ between Outlook on Windows and Outlook on Mac, but both take less than two minutes.
  • Changing your default font does not affect emails you have already sent — only new messages you write from that point forward.
  • If you use Outlook on the web, you can change the font for individual emails but cannot set a permanent default across all messages.

How to set your default font in Outlook on Windows

Open Outlook and go to the File menu in the top left corner. Click Options (near the bottom of the menu). In the Outlook Options window, click Mail on the left side, then scroll down until you see the section labeled Compose Messages.

In that section, look for a button that says Stationery and Fonts. Click it. A new window opens with three tabs: Personal Stationery, Signatures, and Fonts. Click the Fonts tab. Under the heading New Mail Messages, you will see a button labeled Font. Click that button to open the font picker.

A dialog box appears showing every font on your computer. Scroll through the list and click the font you want. You can see a preview of how it looks at the bottom of the box. Once you have chosen, click OK. Then click OK again to close the Stationery and Fonts window, and OK one more time to close Outlook Options. Your default font is now set.

How to set your default font in Outlook on Mac

Open Outlook and click Outlook in the menu bar at the very top of the screen. From the dropdown, click Preferences. In the Preferences window, look for an icon that looks like a piece of paper with lines on it — that is the Mail icon. Click it.

In the Mail preferences, click the tab labeled Compose. You will see a section called Compose Messages. In that section, there is a dropdown menu that says Font. Click it and choose the font you want from the list. Below the font dropdown, you can also set the font size if you want text larger or smaller than the default.

Once you have chosen your font and size, close the Preferences window by clicking the red circle in the top left corner. Outlook saves your choice automatically. The next time you start a new email, your selected font will appear.

What happens if you change your default font partway through

If you change your default font, only new emails you write after the change will use the new font. Any emails you have already sent keep their original font — you cannot go back and change them. If you are in the middle of composing an email when you change your default, that email might not update to the new font until you close and reopen it.

If you want to use a different font for just one email without changing your default, you can. Highlight the text in your message, then use the font dropdown in the toolbar at the top of the compose window. That change affects only that one message.

Why some recipients might not see your chosen font

If you set your default font to something unusual or very new, there is a chance the person reading your email does not have that font installed on their computer. When that happens, their email program substitutes a different font automatically — usually something like Arial or Times New Roman. Your message still arrives and reads fine, but it might look different than you intended.

To avoid this, stick with web-safe fonts that almost every computer has: Arial, Calibri, Times New Roman, Verdana, or Georgia. These fonts are so common that nearly every email program recognizes them. If you use a specialty font, there is no harm done — the recipient will still read your message — but the appearance might shift.

Changing your default font in Outlook on the web

Outlook on the web (the version you access through a browser at outlook.com or through your workplace portal) does not have a permanent default font setting. Instead, you choose a font each time you compose a message. When you click New Message, a compose window opens. Look for the formatting toolbar — it usually appears below the subject line. Click the font dropdown (it often shows the current font name) and pick the one you want for that email only.

If you use Outlook on the web regularly and want a consistent look, the workaround is to always pick the same font manually. There is no way to make Outlook on the web remember your choice across sessions, but you can develop the habit of selecting your preferred font at the start of each message.

Troubleshooting: Your default font is not changing

If you have set a default font but your emails still appear in a different typeface, the most common cause is that you changed the font in the wrong place. Make sure you went to File > Options > Mail > Stationery and Fonts > Fonts tab, and that you clicked the button under New Mail Messages, not Replying or Forwarding Messages. Those are two separate settings.

Another possibility is that you are using a font that your email program does not recognize. Try switching to a standard font like Arial or Calibri to test whether the setting itself is working. If a standard font takes effect but your chosen font does not, the font may be corrupted or not properly installed on your computer.

If you are still stuck, close Outlook completely and reopen it. Sometimes Outlook needs a full restart to explore font changes. If that does not work, restart your computer — this clears Outlook's memory and forces it to reload all settings from scratch.

Frequently Asked Questions

Can I set different default fonts for different email accounts?

No. Outlook uses one default font setting for all accounts you have added to the program. If you need different fonts for different accounts, you will have to change your default each time you switch accounts, or manually select a font for each message.

Does changing my default font affect emails I have already received?

No. Your default font only controls how new emails you write appear. Emails in your inbox keep whatever font the sender used. Changing your default does not change how old messages look.

What if my workplace requires a specific font for all emails?

Set that font as your default using the steps above. Everyone in your organization will then see your emails in the required typeface. If your workplace also requires a signature with specific formatting, you can set both the font and the signature in the same Stationery and Fonts window.

Can I set a default font size along with the font?

Yes, but only on Mac. In Outlook on Mac, the Compose preferences let you set both font and size together. On Windows, you set the font in Stationery and Fonts, but the size is controlled separately in the main compose toolbar — you can change it for each message, but there is no permanent default size setting.

What happens if I delete a font after setting it as my default?

If you uninstall a font that you set as your default, Outlook will fall back to Calibri or Aptos the next time you compose an email. To avoid this, set your default to a font that comes built into Windows or Mac — these are rarely uninstalled by accident.