How to Add a Clickable Phone Number to Your Email Signature (2026 Guide)

The HTML Code: Making Your Phone Number Clickable

To ensure your phone number can be dialed with a single tap on a mobile device, you need to format it as a link using the tel: protocol.

Just like a website link starts with https:, a telephone link starts with tel:. This tells the operating system (iOS, Android, macOS, or Windows) to open the default phone or dialing application (like FaceTime or Skype on desktop).

Basic Click-to-Call HTML

Here is the basic HTML snippet to create a clickable phone number:

<a href="tel:555-123-4567">555-123-4567</a>

Best Practice: International Format

For maximum compatibility, especially if you have international clients, it is highly recommended to use the international dialing format (E.164) inside the href attribute. You can still display the local format to the user:

<a href="tel:+15551234567">(555) 123-4567</a>

[!TIP]

Want people to text you instead? You can use the sms: protocol instead of tel:. For example: Text Me. When clicked, this will automatically launch the user's default messaging app.

How to Remove the Blue Underline (The Developer Way)

If you just drop a plain text phone number into an email, Apple Mail, iOS, and Outlook will automatically turn it into a bright blue, underlined link. They do this because they detect the number pattern and want to make it helpful for the user.

Unfortunately, this automatic styling can clash horribly with your brand colors.

The secret to preventing this is to link the phone number yourself and apply specific inline CSS styles to override the email client's default link colors.

The Ultimate Styled Phone Link

Use this HTML structure to style your phone number, match your brand color (e.g., a nice slate gray), and remove the underline:

<a href="tel:+15551234567" style="color: #4A5568; text-decoration: none !important; font-weight: bold;">

(555) 123-4567
</a>

By adding text-decoration: none !important;, you force strict email clients like Gmail to drop the underline, keeping your signature looking clean and professional.

Which Phone Numbers Should You Include?

Choosing which numbers to share depends heavily on your role and industry. Here is a quick breakdown of best practices:

• Sales & Account Management: Include your direct office line or cell phone. Accessibility is your greatest asset.

• Customer Support: Do *not* include your personal direct line. Instead, link to the main company support line (e.g., 1-800-COMPANY) to ensure tickets go through the proper routing channels.

• Executives: Include the office line and optionally an extension. Cell phones should typically be reserved for internal signatures.

Internal vs. External Signatures

Many professionals use two different signatures.

• Internal Signature (for coworkers): Includes your cell phone number and direct extension for fast collaboration.

• External Signature (for clients/public): Only includes the main company line or a dedicated sales line.

[!NOTE]

The Easier Way to Build Your Signature

Writing HTML and dealing with inline CSS quirks across 40+ different email clients can be exhausting. If you want to skip the code and just get a beautiful, click-to-call signature in 2 minutes, try the InboxSign Email Signature Generator.

Our generator automatically handles the tel: links, completely removes the ugly blue underlines, and ensures your phone numbers look perfectly branded on every device. Best of all? It's completely free and has no watermarks.

Adding a Phone Number in Popular Email Clients

If you aren't writing HTML and just want to add a link using your email client's visual editor, the process is simple:

• Gmail: Highlight your phone number, click the "Link" icon (or press Ctrl/Cmd + K), and type tel:555-123-4567 into the URL box.

• Outlook: Highlight the text, click the "Link" button, and enter tel:555-123-4567 as the address.

• Apple Mail: Highlight the text, right-click, select "Add Link", and enter your tel: protocol link.

Summary

Adding a phone number to your email signature is one of the easiest ways to improve your professional accessibility. Remember to always use the tel: protocol for click-to-call functionality, style your links with inline CSS to prevent the default blue underline, and use the international dialing format for maximum compatibility.

If you don't want to mess with code, you can always rely on a tool like InboxSign to handle the technical details for you.