There are two different types of fonts available to email designers for their emails: web safe fonts and web fonts. For web safe fonts, think of examples like Arial, Times New Roman, Verdana, or Georgia. They’re the default fonts found across the majority of different operating systems and devices. Web fonts aren’t found as part of the default fonts available on various devices and operating systems. A couple of web fonts you may be familiar with are Open Sans and Roboto.

Even though web fonts open up a variety of different design opportunities for web designers, email marketers need to proceed with caution because, unfortunately, not all email clients support web fonts. This is why, when using web fonts, it’s essential to have a fallback web safe font in place for email clients that don’t support web fonts. Think of this as a prioritized list of preferred fonts. If a client can’t comply with your number one choice, it will fall back to the next one on your list.
Make sure to use an Email Service Provider (ESP) that offers the possibility to code your emails and set up your fallback fonts:
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Setting up fallback fonts when using web fonts will allow you to ensure your email rendering is close to what you want, even if your first choice isn’t available.