These days, most people read email on their phones. In fact, a large share of email opens happens on mobile devices (some studies report 26–78% of opens on mobile) . Alarmingly, about 50% of people will delete an email if it isn’t optimized for their phone . To capture and hold attention in 2025, your emails Responsive, Single-Column Layout: Design your email in a single-column format so it naturally fits narrow screens. Multi-column designs often break on mobile.
Use media queries to adjust padding and font sizes on smaller screens. Keep the overall width around 600px, which works well on both desktop and mobile. Readable Fonts: Use sufficiently large text. Headlines should be ~22px or more, and body text at least 14px. This ensures readability without zooming. Also use a legible font (sans-serif fonts like Arial, Helvetica or system fonts) and avoid fancy scripts that are hard to read on small screens. Touch-Friendly Buttons: Make buttons big enough to tap with a thumb.
A height of ~44px is a good target, with extra padding. Ensure links have enough spacing between them. Call-to-action buttons should be full-width or near it, with high contrast against the background. Label them with clear action (e.g. “Download Now” or “Get My Discount”). Short, Punchy Copy: Mobile readers scroll quickly, so keep copy concise. Front-load the important message (“headline above the fold”). Use short paragraphs and bullet points. Highlight key points in bold.
Many users scan, so make your email scannable . Images That Scale: Set images to width:100% so they shrink on small screens. Use compressed images (keep file size as low as possible) to speed loading. Also include alt text for images, since some email clients hide images by default. Alt text provides context (and accessibility) if images don’t load. Minimal Design Elements: Avoid sidebars or extraneous columns that won’t adapt. Simple is best. Remove extra borders or complex backgrounds that might not render well.
A plain background with good contrast is safer for mobile readability (and also handles dark mode better). Dark Mode Compatibility: Many devices now default to dark mode. Use neutral backgrounds and avoid relying on images that contain text (text in images can invert poorly). You can design with darker text on transparent backgrounds to look okay in both modes. Test your emails in dark mode (there are tools or simply enable dark theme on a device).39
Test, Test, Test: Preview your email on actual phones (both iOS and Android) to catch any issues. Simulators or email testing tools can help, but nothing beats a real-device check. Verify the email renders well, links are tappable, and important content isn’t cut off. Remove Small Touch Targets: If your email has navigation links or footers, ensure the text isn’t too small to tap. Tiny links often frustrate mobile users.
Avoid Desktop-Only Content: Elements like hover menus, mouse-over effects, or embedded videos (that open inline) may not work on mobile. For embedded videos, consider a thumbnail image that Quick Loading: Assume some subscribers have slower connections. Limit heavy code (like multiple background images) and remove hidden elements that increase load. Emails should ideally be under ~100 KB for good speed.
One-Click Actions: If your email requires a conversion (like making a purchase or signing up), try to minimize steps. For example, mobile-friendly landing pages are a must if you link out. By following these guidelines, your emails will look polished and be easy to engage with on any device. Remember: a bad mobile experience can be fatal to your campaign. About half of readers will toss an email that’s hard to use .
But by designing “mobile-first” — large text, big buttons, simple layout — you ensure more readers stay and click. The effort pays off: a mobile-optimized email campaign reaches more people and drives more results.