You've worked hard on your brand, creating a logo, choosing a color palette, and maybe even finding a custom font that fits your style. But should you use that custom font in your email newsletter?
The short answer is no, and here's why. The font on your website is called a web font. Web fonts work because browsers download them using the @font-face CSS rule, a standard every modern browser supports.
Email clients don't work the same way. Can I Email reports that only 24% of email clients support the @font-face CSS rule that allows custom fonts. This isn't weighted by market share, but the takeaway is simple: about three out of four email clients won't display your custom font.
For consistent and reliable rendering, email-safe fonts are a better bet.
What email-safe fonts are and why they matter
Email-safe fonts (also called web-safe fonts) are typefaces that come pre-installed on virtually all operating systems and devices. They render consistently because the recipient's device already has them, so there's nothing to download.
The widely accepted email-safe fonts are:
- Arial and Helvetica (sans-serif)
- Georgia and Times New Roman (serif)
- Verdana, Tahoma, and Trebuchet MS (sans-serif)
- Courier New (monospace)
The generic families sans-serif, serif, and monospace also work as final fallbacks, though they'll resolve to different fonts on different systems.
Custom web fonts aren't pre-installed on most devices, and email client support varies widely. Apple Mail is the exception here, with full @font-face support and the highest compatibility score on Can I Email's scoreboard. Most other clients aren't as generous.
What happens when a web font fails
When an email client doesn't support @font-face, it works through the font stack you've specified. If your email's styles say font-family: 'Open Sans', Arial, sans-serif, the client tries Arial instead. If Arial isn't available, it falls to the generic sans-serif.
That sounds like a reasonable safety net, but fallback fonts aren't always a clean swap. Different fonts have different character widths, heights, and line heights. A fallback that's wider or taller than the original can break button layouts or throw off a responsive design.
How to choose the right email-safe font
You have more range here than you might think.
Arial and Helvetica are the safe defaults for a clean, modern look. Helvetica is slightly more refined, but Arial is what Windows falls back to, so it's the more universal choice.
Georgia is the go-to serif option. It was designed for screen readability and holds up well in content-heavy newsletters where you want a warmer, editorial tone.
Verdana is worth considering if readability is your priority. Its wide characters and generous spacing make it easier to read at smaller sizes.
Courier New covers monospace, which is great for technical or code-heavy emails.
Whichever font you pick, always include a generic fallback at the end of your font stack (Arial, sans-serif, Georgia, serif). Stick to ~16px for body text and keep good contrast between the text color and background.
Sendfully's email editor includes a set of email-safe fonts with the appropriate generic fallbacks already built in. You don't have to think about font stacks.
The practical choice for now
Email-safe fonts look the same everywhere and load instantly. You still have plenty of room to create a distinct look. Font size, weight, line height, letter spacing, and color are all fully supported across email clients. And familiar typefaces are the easiest to read, according to WebAIM research.
If @font-face support improves across email clients, web fonts will be worth revisiting. Until then, the classics will keep your newsletters looking great in every inbox.