Email Signature Best Practices

What to Include in Your Email Signature

Every email signature strikes a balance between being informative and staying concise. Start with the essentials, then add optional elements only when they serve a clear purpose for your audience.

Essential Elements

• Full name
• Job title
• Company name
• Phone number (one primary number)
• Email address

Optional Elements

• Headshot photo
• Company logo
• Website URL
• Social media links (LinkedIn, Twitter/X)
• Physical address
• Pronouns
• Professional certifications or credentials

What NOT to Include

Just as important as knowing what to include is knowing what to leave out. These elements add clutter, create compatibility issues, or undermine your professionalism.

• Inspirational quotes— unprofessional in most business contexts and can distract from your contact information.
• Multiple phone numbers— pick one primary number. Listing several creates decision fatigue for the recipient.
• Animated GIFs— they break in most email clients, increase file size, and appear unprofessional.
• Large banner images— they increase email size significantly and are often blocked by default in corporate email clients.
• Legal disclaimers longer than the signature itself — if your company requires a disclaimer, keep it short or link to a full version on your website.
• Unsubscribe links— not appropriate for personal or one-to-one email signatures; these belong in marketing emails only.

Email Signature Dimensions

Keeping your signature within these recommended dimensions ensures it displays correctly across desktop and mobile clients without overwhelming the email body.

Design Tips

Good signature design is about clarity and restraint. These guidelines help you create a signature that looks polished without overcomplicating the layout.

• Use no more than 2–3 brand colors to maintain visual consistency.
• Stick to 1–2 fonts: one for your name or headings, one for body text.
• Use a visual separator (a vertical line, color block, or subtle divider) between your name and contact details.
• Left-align textfor readability — centered signatures are harder to scan.
• Keep line height at 1.4–1.6so text doesn't feel cramped.
• Use table-based HTMLfor email client compatibility — never rely on div-based or flexbox layouts in email signatures.

Email Client Compatibility

Email clients render HTML very differently from web browsers, and this is the single biggest source of broken signatures. Microsoft Outlook on Windows uses the Word rendering engine, which strips or ignores most modern CSS properties including flexbox, grid, float, and many shorthand declarations. Gmail strips <style>blocks and rewrites class names, so any CSS that isn't inlined will be lost. Apple Mail is the most permissive of the major clients and supports a broader range of CSS, but you can't design for Apple Mail alone.

The safest approach is to use table-based layouts with inline styles on every element. This ensures your signature looks consistent whether your recipient opens it in Outlook 2016, Gmail on the web, Apple Mail on macOS, or a mobile email app. Avoid external stylesheets and embedded <style>blocks entirely — most email clients will strip them.

Mobile Considerations

More than half of all emails are now opened on mobile devices. Your signature needs to remain legible and functional on smaller screens.

• Signatures should be readable without zooming on mobile screens.
• Use font sizes of at least 12px for body text — anything smaller becomes difficult to read on mobile.
• Ensure links and phone numbers are tappable with a minimum 44px touch target so users can interact without frustration.
• Test your signature by sending yourself a test email and opening it on your phone before rolling it out.
• Avoid fixed-width layouts wider than 320pxfor the mobile viewport — use percentage-based widths or a max-width approach instead.

Common Mistakes to Avoid

1. Using an image-only signature. If your entire signature is a single image, it will be blocked by default in many email clients, leaving the recipient with nothing.
2. Including too much information. A signature with six phone numbers, three addresses, and a paragraph-length tagline overwhelms the reader and buries the essential details.
3. Forgetting to test across email clients. A signature that looks perfect in Apple Mail can be completely broken in Outlook. Always test in at least two or three clients.
4. Using web fonts. Custom web fonts are not supported in most email clients. Stick to system-safe fonts like Arial, Helvetica, Georgia, or Verdana.
5. Linking images without alt text. When images are blocked, alt text is the only thing the recipient sees. Always provide meaningful alt attributes.
6. Making the signature taller than the email. If your signature is longer than your typical message, it undermines the email itself and looks unprofessional.
7. Not updating outdated information. An old phone number or a previous job title in your signature erodes trust. Review your signature at least once a quarter.

Related Resources

• Setup Guides — Step-by-step installation for Gmail, Outlook, Apple Mail, Thunderbird, and Yahoo Mail
• SignForge vs WiseStamp — Detailed pricing and feature comparison
• SignForge vs Exclaimer — Enterprise email signature comparison
• SignForge vs CodeTwo — Server-side vs client-side comparison