How to Change the Default Font in Outlook (All Versions)
Outlook's default font — Calibri 11pt in most installations — wasn't chosen for you personally. It was chosen for everyone. If you spend hours in your inbox daily, that's worth fixing. The good news: changing your default font in Outlook is a straightforward setting buried just a few menus deep. The more nuanced news: where you find it, and what it actually controls, varies depending on your version and how you use email.
What "Default Font" Actually Means in Outlook
Before diving into steps, it helps to understand what you're actually changing. Outlook treats font settings in layers:
- New messages — the font used when you compose a brand-new email
- Replies and forwards — can be set independently from new messages
- Plain text messages — a separate setting, since plain text ignores HTML formatting entirely
- Reading pane — some versions let you adjust how received emails render on your screen, though this doesn't affect what recipients see
Changing the default font affects your outgoing composition experience and the formatting recipients see (for HTML emails). It does not reformat emails others send to you — those display in the sender's chosen font unless you've specifically adjusted reading pane overrides.
How to Change the Default Font in Outlook for Windows 🖥️
This applies to Outlook as part of Microsoft 365 and standalone versions (Outlook 2016, 2019, 2021).
- Open Outlook and go to File → Options
- Select Mail from the left panel
- Under the Compose messages section, click Stationery and Fonts
- You'll see three tabs:
- Personal Stationery — this is where font defaults live
- Theme — for background/design templates (separate from font)
From the Personal Stationery tab:
- Click Font under New mail messages to set the font for emails you compose from scratch
- Click Font under Replying or forwarding messages to set a separate style for replies
- Each opens a standard font dialog — choose your font face, style (regular, bold, italic), size, and color
- Click OK through each dialog to save
Plain text font is set separately: still in Mail Options, look for Compose messages in this format — if set to plain text, the font dialog under Stationery won't apply. Plain text font is adjusted via a different control in the same Options panel.
How to Change the Default Font in Outlook for Mac 🍎
The path differs slightly in Outlook for Mac (Microsoft 365 version):
- Open Outlook → go to Outlook in the top menu bar → Preferences
- Select Fonts
- You'll see options for:
- HTML messages (new, reply, and forward)
- Plain text messages
- Click Choose next to each to open the system font picker
- Select your preferred font, size, and style, then close the panel — changes save automatically
Note: Outlook for Mac uses the macOS native font panel, which looks and behaves differently from the Windows dialog but offers the same core controls.
Outlook on the Web (OWA)
If you use Outlook through a browser at outlook.com or via your organization's Microsoft 365 portal, font defaults work differently:
- Click the Settings gear (top right)
- Go to Mail → Compose and reply
- You'll find a formatting toolbar where you can set the default font, size, and color for new messages
- Save your changes
OWA's settings are stored in the cloud, so they follow you across devices and browsers — unlike the desktop app, where settings are local to that installation.
New Outlook for Windows (2024 and Later)
Microsoft has been rolling out a redesigned "New Outlook" app that more closely mirrors OWA. If you've switched to the new experience:
- Click Settings (gear icon)
- Navigate to Mail → Compose and reply
- Use the formatting bar to set your default font preferences
The interface is nearly identical to OWA, reflecting Microsoft's convergence of the two products.
Key Variables That Affect Your Experience
| Factor | What It Changes |
|---|---|
| Outlook version (classic vs. new) | Where settings live and what options are available |
| Windows vs. Mac | Different menus, font pickers, and save behaviors |
| Desktop vs. web | Local settings vs. cloud-synced preferences |
| HTML vs. plain text mode | Font settings apply only to HTML; plain text ignores them |
| Organization IT policies | May lock or override font settings in managed environments |
When Your Font Change Doesn't Seem to Stick
A few common reasons font changes don't apply as expected:
- You changed new message font but not reply font — they're independent settings in the desktop app
- Your organization uses email templates or signatures — these may apply their own formatting on top of your defaults
- The email is in plain text mode — check the Format Text tab in a new message to confirm you're composing in HTML
- Managed IT environment — Group Policy settings can override user-level font preferences in corporate deployments
The Part That Depends on Your Situation
The mechanics above are consistent. What varies is which combination of settings actually solves your problem — and that depends on factors only you can assess: which version of Outlook you're running, whether you're on a personal or managed device, whether you compose primarily in HTML or plain text, and whether you need font changes to apply to replies differently than new messages. The steps are the same; the right combination of them isn't.