Email marketing remains a critical channel for brands to reach UK consumers30% of brands in L2’s Digital IQ Index: Beauty UK receive more site traffic from email than social platforms or display advertising. However, less than half of the brands in the study optimize their email campaigns for viewing on mobile devices.

Winning brands incorporate mobile viewers into campaign strategies by using shorter subject lines and creating email content that falls above the fold on a mobile screen. For email subject lines, iPhones have a display limit of 38 characters (roughly five to seven words). Yet in 2017, the average subject line for brands in L2’s UK study contained 42 characters. Brands that use 20-30 characters in email subject lines achieve an average open rate of 21%. When the subject line length increases to 39-50 characters, that rate falls to 15% almost a third lower than the open rate enjoyed by mobile-friendly brands.


Soap & Glory boasts the highest open rate in L2’s study: 31%.
The brand uses email to share tutorials with consumers and drive buzz around product launches. Soap & Glory also ensures that emails are mobile-friendly, with short subject lines (29 characters, on average) for over 75% of emails.


In contrast, Smashbox has one of the lowest open rates in the Index: 11%. Only 25% of Smashbox’s email subject lines are length-optimized for mobile readability. Additionally, Smashbox’s creatives are often cut off by the mobile fold, creating a disjointed experience for users.

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