How to Change the Default Font in Outlook (2026 Guide)

If you've ever opened a new email in Outlook and found yourself staring at the same default typeface — usually Aptos or Calibri, depending on how recently your account was updated — you already know how easy it is to feel stuck with it. The good news: Outlook lets you set a permanent default font for new messages, replies, and forwards, so you never have to manually reformat every email you send.

The catch is that Microsoft has rebuilt Outlook's settings menu several times over the past few years, so the steps depend heavily on which version you're using: classic Outlook for Windows, the new Outlook for Windows, Outlook for Mac, or Outlook on the web. This guide walks through all four.

Not sure which version you have? If you see a File tab in the top-left corner, you're on classic Outlook. If you only see a gear icon and a row of icons down the left side, you're on the new Outlook or the web app.

Before diving in, it helps to confirm your version, since the menus look completely different:

Classic Outlook gives you the most control — you can set separate fonts for new messages, for replies and forwards, and even for plain-text emails.

1. Open Outlook and click File in the top-left corner.

2. Select Options.

3. In the left-hand menu, click Mail.

4. Under the "Compose messages" section, click Stationery and Fonts…

5. In the Signatures and Stationery window, under New mail messages, click Font…

6. Choose your preferred font family (e.g., Calibri, Arial, Aptos), style, size, and color, then click OK.

7. Repeat the process under Replying or forwarding messages if you want a different font for replies.

8. Click OK two more times to close the remaining windows and apply your changes.

Your new default will apply immediately to any new email or reply you compose.

Tip: If the Font… button is greyed out, Outlook is likely using a stationery theme instead of a plain font. Switch the "Theme or stationery for new HTML e-mail message" option to (No theme) or check Always use my fonts, then try again.

The new Outlook (the streamlined version Microsoft has been rolling out to replace classic Outlook) moved font settings out of a dedicated dialog box and into the main Settings panel.

1. Open the new Outlook and click the Settings gear icon in the top-right corner.

2. Select View all Outlook settings (or Mail in the left-hand list, depending on your build).

3. Choose Compose and reply.

4. Under Message format, you'll see your current default font. Click it to open the font picker.

5. Select the font, size, and style you want.

6. Click Save at the bottom of the panel.

Keep in mind this setting only affects messages formatted as HTML. If you compose in plain text, Outlook will use your system's plain-text default instead.

Outlook on the web (outlook.office.com or outlook.live.com) uses essentially the same settings panel as the new Outlook for Windows, since they share the same underlying interface.

1. Click the gear icon in the top-right corner of the browser window.

2. Select View all Outlook settings or Mail.

3. Go to Compose and reply.

4. Under Message format, choose your preferred font and size.

5. Click Save.

This setting is global for your account — there's no separate tab for replies versus new messages on the web version, so whatever you choose applies everywhere you compose.

Outlook for Mac keeps font settings in its own dedicated Fonts pane, separate from the general Preferences.

1. Open Outlook and click Outlook in the top menu bar, then Settings (or Preferences on older versions).

2. Click Fonts.

3. Under New mail, click the Font… button.

4. Choose your typeface, style, and size, then confirm your selection.

5. Under Reply or forward, click Font… and repeat the process if you want a different font for replies.

6. Close the Settings window — changes save automatically.

Note that classic Outlook for Mac doesn't have a separate setting for plain-text emails; those will always use your Mac's system default font.

"I don't have a File menu." You're on the new Outlook or the web app — use the Settings gear instead.

"The Font… button is greyed out (classic Outlook)." Your stationery theme is overriding manual font choices. Set the theme to "(No theme)" or enable "Always use my fonts."

"My changes aren't sticking." On the new Outlook or web, double check you clicked Save at the bottom of the settings panel before navigating away.

Setting a default font in Outlook takes about two minutes once you know where to look — the challenge is really just tracking down the right menu for your version. Whether you're standardizing on your company's brand typography or simply want something easier on the eyes, the steps above should have you set up in whichever version of Outlook you're using.