How to Change Your Signature Block in Outlook

Whether you're updating a job title, swapping phone numbers, or building a professional email signature from scratch, Outlook gives you solid tools to manage how your name and contact details appear at the bottom of every message. The process varies slightly depending on which version of Outlook you're using — and that distinction matters more than most people realize.

What Is a Signature Block in Outlook?

A signature block (or email signature) is the block of text — and sometimes images or logos — that Outlook automatically appends to your outgoing emails. It typically includes your name, job title, company, phone number, and sometimes a legal disclaimer or social media links.

Outlook lets you create multiple signatures and assign them to different scenarios: one for new emails, another for replies and forwards, and even different signatures for different email accounts if you manage more than one inbox.

Which Version of Outlook Are You Using?

Before diving into steps, it helps to know that "Outlook" covers several different products:

The signature editor works differently in each. Steps that apply to Classic Outlook won't always match New Outlook or the web version.

How to Change Your Signature in Classic Outlook (Desktop) ✉️

This is the most feature-rich signature editor Outlook offers.

1. Open Outlook and go to File → Options
2. Select Mail from the left-hand panel
3. Click the Signatures… button (under the "Compose messages" section)
4. In the Signatures and Stationery dialog, select an existing signature from the list to edit it — or click New to create one
5. Edit your text in the editor at the bottom of the window
6. Use the formatting toolbar to adjust font, size, color, or alignment
7. To add an image (like a logo), click the picture icon in the toolbar
8. Under Choose default signature, set which signature applies to New Messages and which applies to Replies/Forwards — per account if needed
9. Click OK to save

The Classic desktop editor is the most capable: it supports HTML formatting, embedded images, hyperlinks, and fine-grained font control.

How to Change Your Signature in New Outlook (Desktop)

Microsoft's redesigned Outlook app uses a different path:

1. Go to Settings (gear icon, top-right)
2. Select Accounts → Signatures
3. Choose an existing signature or create a new one
4. Edit in the text area provided
5. Toggle on Automatically include my signature if you want it appended by default
6. Save your changes

The New Outlook signature editor is simpler than Classic — formatting options are more limited, and some users find it less flexible for complex signatures with logos or multi-column layouts.

How to Change Your Signature in Outlook on the Web

1. Click the Settings gear icon (top-right corner)
2. Select View all Outlook settings at the bottom of the panel
3. Navigate to Mail → Compose and reply
4. Scroll to the Email signature section
5. Edit the text directly in the editor
6. Toggle whether to automatically include the signature on new messages and/or replies
7. Click Save

Web-based signatures sync with your Microsoft 365 account, but they're stored separately from your desktop app signature. Changing one doesn't automatically update the other.

How to Change Your Signature in Outlook for iOS or Android 📱

Mobile signatures in Outlook are plain text only — no HTML formatting or images.

1. Open the Outlook app
2. Tap your profile icon (top-left)
3. Tap the gear icon to open Settings
4. Scroll to Signature under the Mail section
5. Tap to edit and type your desired signature text
6. Changes save automatically

If you use Outlook on both desktop and mobile, be aware that these are separate signatures — updating one won't affect the other.

Common Variables That Affect Your Signature Setup

The "right" way to set up a signature depends on factors specific to your situation:

• Number of email accounts: Multiple accounts can each have their own default signature in Classic Outlook — useful if you manage work and personal email from the same app
• Image and logo use: HTML signatures with embedded images display well in most modern clients, but can break or show as attachments in some older or plain-text email environments
• Plain text vs. HTML: Some organizations or industries default to plain-text email, where rich formatting won't render as intended
• IT policy and managed accounts: Corporate Exchange or Microsoft 365 accounts sometimes apply server-side signatures (set by IT administrators), which may override or supplement what you configure locally
• Signature length and content: Legal disclaimers, social links, or certification badges are common in professional contexts but may not suit every use case

What "Default" Signature Actually Means

Outlook's default signature setting determines automatic insertion — whether your signature appears in every new email and/or every reply without you manually adding it. You can also choose no default and insert a signature manually per message using the Insert → Signature menu when composing.

This matters for users who send emails in different contexts — a formal signature for clients, a minimal one for internal colleagues — and want control over which appears when.

A Note on Syncing Across Devices 🔄

One area that trips up many users: Outlook does not universally sync signatures across devices and platforms. Your Classic desktop signature, New Outlook signature, web signature, and mobile signature can all be different — and usually are, unless you manually replicate them. For users who work across multiple devices, that means signature consistency requires deliberate management, not an assumption that one change covers everything.

The right approach depends on how many devices you use, which versions of Outlook you're running, and how much consistency matters for your professional or personal communication style.