Mar 19, 2026

How to Add a Signature in Outlook (Every Platform, 2026)

Outlook Email Signature Outlook Signature Microsoft 365 How-to Email

Outlook supports email signatures across every platform — web, desktop, and mobile — but the steps to create and manage them differ in each. If you use Gmail instead, see how to add a signature in Gmail. This guide covers all four Outlook versions, plus how to set different signatures for new emails vs. replies, add images, and insert hyperlinks.

1. Outlook on the Web (Microsoft 365)

Go to outlook.office.com and sign in with your Microsoft account.
Click the gear icon in the top right corner.
Click View all Outlook settings at the bottom of the panel.
Go to Mail → Compose and reply.
Under Email signature, click + New signature.
Give your signature a name (e.g., “Work” or “External”).
Type or paste your signature content in the editor. Use the formatting toolbar to bold text, change fonts, add links, and insert images.
Under the editor, use the For new messages dropdown to select this signature as the default for new emails.
Use the For replies/forwards dropdown to set a default for replies (or choose No signature to keep replies clean).
Click Save.

You can create multiple signatures and switch between them. When composing an email, click the three dots (…) in the toolbar → Insert signature to pick a different one on the fly.

2. New Outlook Desktop App (Windows/Mac)

The new Outlook app (the one Microsoft is migrating everyone to) shares the same settings interface as Outlook on the web.

Open the new Outlook app and click the gear icon in the top right.
Click View all Outlook settings.
Go to Mail → Compose and reply.
Under Email signature, click + New signature and give it a name.
Compose your signature in the rich text editor.
Set your defaults using the For new messages and For replies/forwards dropdowns.
Click Save.

If you already set up a signature in Outlook on the web, it will already be here — the new desktop app and web app share the same signature store.

3. Classic Outlook for Windows

Classic Outlook (the version with the ribbon toolbar and File menu) uses a separate signature system.

Open Outlook and go to File → Options.
Click Mail in the left sidebar.
Click the Signatures… button.
In the Signatures and Stationery dialog, click New.
Name your signature and click OK.
In the Edit signature box at the bottom, type your signature content. The formatting toolbar above the editor lets you change fonts, colors, alignment, and add images or hyperlinks.
Under Choose default signature, select your email account from the E-mail account dropdown.
Set the New messages dropdown to your preferred signature.
Set the Replies/forwards dropdown — choose a shorter version or none if you don’t want your full signature appended to every reply.
Click OK.

To switch signatures while composing, go to the Insert tab in the ribbon and click Signature → select the one you want.

4. Outlook Mobile App (iOS/Android)

Open the Outlook app on your phone.
Tap your profile icon in the top left corner.
Tap the gear icon to open Settings.
Scroll down to the Mail section and tap Signature.
Edit the default text (“Get Outlook for iOS/Android”) and replace it with your own.
On iOS, tap the back arrow to save. On Android, tap the checkmark.

The mobile signature editor is plain text only — no images, no hyperlinks, no formatting. If you need a formatted signature on mobile, compose it in HTML elsewhere and paste it into the field, but rendering varies across recipients’ email clients.

On iOS, you can toggle Per Account Signature to set a different signature for each email account connected to the app.

5. Set Different Signatures for New Emails vs. Replies

Most professionals want their full signature (name, title, logo, booking link) on new emails but something shorter — or nothing — on replies and forwards in a long thread. Outlook supports this on every platform except mobile.

Outlook on the web / new Outlook desktop:

Under Mail → Compose and reply, use the two dropdowns beneath your signature list: For new messages and For replies/forwards. Set each to a different saved signature or to (No signature).

Classic Outlook for Windows:

In the Signatures and Stationery dialog, the Choose default signature section has the same two dropdowns: New messages and Replies/forwards.

Outlook on Mac (classic):

Go to Outlook → Settings → Signatures. Select a signature and check or uncheck the boxes for New messages and Replies and forwards.

A common setup: use your full signature with logo and booking link for new messages, and a stripped-down version (just your name and phone number) for replies.

6. Add an Image or Logo to Your Signature

Outlook on the web / new Outlook desktop:

In the signature editor under Mail → Compose and reply, place your cursor where you want the image.
Click the image icon in the formatting toolbar.
Select Insert images inline and upload your file.

Classic Outlook for Windows:

In the Signatures and Stationery dialog, place your cursor in the Edit signature box.
Click the image icon in the toolbar.
Browse to your image file and click Insert.

Classic Outlook for Mac:

Go to Outlook → Settings → Signatures.
Drag and drop your image into the signature editor, or paste it from the clipboard.

Sizing tips:

Keep your logo under 300 pixels wide and 100 KB in file size. Larger images get clipped or blocked by recipients’ email clients.
Use PNG for logos with transparency, JPG for photos.
Some email clients block images by default. Always include a text fallback (your company name as plain text) so your signature still makes sense without the image.

7. Add a Hyperlink to Your Signature

Adding a clickable link — whether it’s your website, LinkedIn profile, or a scheduling link — works the same way across Outlook’s rich text editors.

Type the text you want to display (e.g., “Book a meeting with me” or “usecarly.com”).
Highlight the text.
Click the link icon in the formatting toolbar (or press Ctrl+K on Windows, Cmd+K on Mac).
Paste the URL and click OK.

This works in Outlook on the web, the new Outlook desktop app, and classic Outlook for Windows and Mac. It does not work in the Outlook mobile app, which only supports plain text signatures.

What to link:

Your booking/scheduling page — this is the single highest-value link in any email signature. If you use Carly, you can generate a free booking page that checks your real-time calendar availability, then add it to your signature so every email you send becomes a scheduling opportunity.
Your company website
Your LinkedIn profile

Stick to two or three links maximum. A signature crammed with links looks cluttered and can trigger spam filters.

8. Troubleshooting Common Signature Issues

Signature not appearing on replies: Check that your Replies/forwards default is set to a signature, not (No signature). This is the most common fix.

Images not showing for recipients: The recipient’s email client may block external images by default. Host your logo on a reliable server (your company website or a CDN) and reference it via URL rather than embedding it — embedded images increase email size and are more likely to be stripped.

Formatting looks wrong in recipient’s inbox: Different email clients render HTML differently. Stick to simple formatting: one or two fonts, basic colors, no complex tables. Test by sending yourself an email and viewing it in Gmail, Apple Mail, and Outlook.

Signature too long: Keep it under six lines of text. Name, title, company, phone, one or two links. That’s it.

Different signature needed per account: In Outlook on the web and desktop, the E-mail account dropdown in signature defaults lets you assign different signatures to different accounts. On mobile iOS, toggle Per Account Signature in settings.

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