If you aren’t tailoring your messages for mobile, listen up.

A new study from email firm Constant Contact, partnering with research firm Chadwick Martin Bailey, finds that most people read their email on mobile devices—and it matters if it’s readable. More details:

First on mobile, then on desktop: If a user reads an email on mobile device, that email doesn’t necessarily end there. While 80 percent of respondents find it “extremely important” to be able to read an email on a smartphone and 75 percent are highly likely to delete an email that can’t be easily read on the device, 79 percent are likely to come back to that email later on another device. In other words, the desktop experience still matters.

The demographic split: When it comes to whether a user is likely to read an email on mobile, age is key. According to the study, 88 percent of people between the ages of 18 and 30, and 85 percent of people between the ages of 30 and 39, open emails on mobile devices. In both cases, around half say a smartphone is their primary email-reading device. But among people over 40, well below 50 percent say that they primarily read email on a mobile device.

So what should marketers know? Simply, that they should write emails that work well in a mobile environment.

“The great thing about mobile emails is that shorter content and fewer calls to action actually perform better than complicated and dense messaging,” Constant Contact’s mobile product manager, Jim Garretson, explained in a press release. “By simplifying email marketing campaigns, marketers can take an essential and effective step towards becoming mobile-friendly.”

How are you improving your mobile email approach? Let us know in the comments below.

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