Short answer:
Email signature design is not like web design. To ensure your signature works across all email clients, you must follow specific limitations and best practices.
Summary:
Email signatures need to balance design and compatibility. This guide explains why signatures behave differently and how to create a design that works reliably across devices and email clients.
Common challenges
Our design team is often asked to help with questions like:
I’ve created our company email signature, but it doesn’t preview correctly on my iPhone.
We want a signature that looks great in all inboxes—desktop, web, and mobile.
If this sounds familiar, you’re not alone.
- Designers focus on visual appearance
- Email signatures must also work across many email clients
Why email signature design is different
Email clients (Outlook, Gmail, Apple Mail, mobile apps, etc.) do not follow modern web standards.
This means:
- A design that looks perfect in one client may break in another
- Full visual consistency across all devices is not possible
Important
Aim for a design that works reliably everywhere—not one that looks identical in every client.
Design for mobile first
Most emails are opened on mobile devices, so your signature should be optimized for smaller screens.
- Use a maximum width of 320px
- Keep layouts simple and easy to scan
Tip: Use a single-column table with a width of 320px as your design foundation.
Use Xink to ensure consistency
Uploading your signature to Xink helps ensure consistent deployment across users and devices.
- Upload your existing signature
- Or use the built-in designer in Xink
Use inline CSS only
Email clients have limited support for modern CSS.
- Avoid external stylesheets and advanced CSS
- Use inline CSS for fonts, colors, and spacing
This is especially important for compatibility with Outlook.
Use the right image format
- Use JPG for general images
- Use PNG when transparency is required
Be aware that some email clients may compress or modify images.
Attachments may occur
Images (such as logos) can sometimes appear as attachments in emails.
This is a limitation of email clients and cannot always be avoided.
Prioritize content placement
The top of your email is the most visible area, especially in preview panes.
- Start with key information (name, title, contact details)
- Avoid placing large images at the top
- Place logos and banners below the main content
Summary
- Design for compatibility over perfection
- Optimize for mobile (320px width)
- Use inline CSS only
- Expect differences across email clients
