How to Add Your Signature in Outlook (Desktop, Web & Mobile)
Adding a signature in Outlook is one of those small setup tasks that pays off every day — every email you send can automatically include your name, title, contact details, or even a company disclaimer. But the exact steps depend on which version of Outlook you're using, and there are more versions than most people realize.
Why Outlook Signatures Work Differently Across Versions
Microsoft offers Outlook across several distinct platforms: the classic desktop app (part of Microsoft 365 or older Office installs), the new Outlook for Windows (a rebuilt app rolling out as a replacement), Outlook on the web (accessed via outlook.com or office.com), and the Outlook mobile app for iOS and Android. Each has its own signature settings, and a signature you create in one won't automatically carry over to another.
This is the most common source of confusion — someone sets up a signature on their desktop and then wonders why it doesn't appear when they reply from their phone.
How to Add a Signature in Classic Outlook (Desktop App)
This applies to Outlook as part of Microsoft 365, Office 2019, Office 2021, and older standalone installs on Windows.
- Open Outlook and go to File → Options → Mail
- Click Signatures… (under the "Compose messages" section)
- In the Signatures and Stationery window, click New to create a signature
- Give it a name (e.g., "Work" or "Personal") — this is just for your reference
- Type and format your signature in the editing box below
- Under Choose default signature, set which email account uses it and whether it applies to New Messages, Replies/Forwards, or both
- Click OK to save
The formatting editor here is basic but functional — you can change fonts, add links, insert an image (like a logo or headshot), and align text. For HTML-formatted signatures, you can also paste formatted content directly from a word processor or browser.
How to Add a Signature in Outlook on the Web 🌐
If you use Outlook through a browser (outlook.com, Outlook Web App, or Microsoft 365 online):
- Click the Settings gear icon in the top-right corner
- Select View all Outlook settings at the bottom of the panel
- Navigate to Mail → Compose and reply
- Scroll to the Email signature section
- Type your signature in the text box
- Toggle on Automatically include my signature on new messages and/or replies and forwards if desired
- Click Save
Web signatures support basic rich text formatting, inline images, and hyperlinks. If you want something more polished, designing the signature in HTML and pasting it in is a common workaround — though the web editor can strip some formatting.
How to Add a Signature in the New Outlook for Windows
The new Outlook for Windows (the version that looks and behaves more like Outlook on the web) follows essentially the same process as the web version above. Go to Settings → Mail → Compose and reply → Email signature. The interface is nearly identical, which is intentional — Microsoft has been aligning the new desktop app with the web experience.
How to Add a Signature in Outlook Mobile (iOS & Android) 📱
The mobile app handles signatures separately from any desktop or web signatures you've set up.
- Open the Outlook app and tap your profile icon in the top-left
- Go to Settings (gear icon at the bottom)
- Tap your email account
- Select Signature
- Edit the text and tap the checkmark or Done to save
Mobile signatures are plain text only in most cases — no images, no HTML formatting. Some users keep a simplified version of their signature here and rely on the desktop or web version for richer formatting.
Key Variables That Affect Your Setup
The right approach depends on several factors that vary by user:
| Variable | Why It Matters |
|---|---|
| Outlook version | Steps differ across classic, new, web, and mobile |
| Number of email accounts | Classic Outlook lets you assign different signatures per account |
| Signature complexity | Images and HTML behave differently across platforms |
| Organization IT policies | Corporate Exchange or Microsoft 365 accounts may have server-side signature rules that override personal settings |
| Device usage pattern | If you reply from multiple devices, each needs its own signature configured |
A Note on Corporate and Managed Accounts 🔒
If your Outlook account is managed by an employer or IT department, your ability to set signatures may be restricted or supplemented by server-side signatures — automatically appended disclaimers or branded footers applied at the mail server level. In these cases, your personal signature settings may still work for new messages, but replies or outgoing mail might get a second signature added by the mail system. If this is happening, it's worth checking with IT before troubleshooting on your own.
Common Formatting Considerations
- Images in signatures: Embedded images sometimes display as attachments for recipients depending on their email client. Hosting the image online and linking to it (rather than embedding) tends to be more reliable.
- HTML signatures: Classic Outlook handles HTML signatures more robustly than the web or new desktop app. If you're copying a designed signature from a third-party signature generator, test it across clients before relying on it.
- Signature for replies vs. new messages: Many users prefer signatures only on new messages, not replies, to reduce clutter in back-and-forth threads. This is a separate toggle in most versions.
The version of Outlook you're using, whether your account is personal or organizational, which devices you send email from, and how polished you need the signature to look — all of these shape which approach actually makes sense for your situation.