Email marketing software company Constant Contact just released a new study looking at open rates, finding that subscriber email domain and industry are major factors. According to the firm, segmented, personalized subscriber lists see higher open rate success and mobile devices now make up over half of all opens.

The study pulls data from over 100 billion emails sent from Constant Contact this year and last.

According to the study, personalized campaigns can result in open rates being raised by 150%. Those sent to 35 people or less (which suggests a more personalized campaign) saw open rates of 55% compared to the average rate of 22%. Those sent to over 7,500 subscribers (lower personalization) averaged about 14%.

“This study provides conclusive proof that personalizing the emails you send, so that you’re speaking directly to specific interests and wants of a subscriber, not only strengthens the relationship with subscribers, it results in better campaign performance,” said Constant Contact chief analytics officer Jesse Harriott. “Small businesses tend to be great at developing authentic customer relationships and this data underscores the marketing value of those relationships.”

As mentioned, the study found subscriber domain to play a significant role. It found that campaigns sent to Comcast, Verizon, and Cox email addresses had the highest open rates. AOL, Hotmail, and Yahoo addresses were at the opposite end of the spectrum.

It also found that nonprofits get higher click-through rates than B2C and B2B campaigns. They also get better open rates. The average is 29% compared to 23% for B2C and 20% for B2B.

Here’s a look at industry:

“Whether it’s a religious organization or school, nonprofits generally have a passionate and engaged subscriber base that enjoys seeing regular updates and communications,” said Harriott. “However, the data also shows that—with the right type of execution—it is possible for businesses to replicate that kind of engagement. For example, if a fitness center keeps tabs on which exercise classes their members have taken in the past, sending relevant upcoming class schedules to the right members will inevitably result in higher open rates and well attended classes.”

51% of all emails are opened on either a smartphone or tablet, the study found. 38.8% are opened on a smartphone and 11.9% are opened on a tablet.

“Constant Contact has found that three-quarters of subscribers say they will delete an email if they can’t read it on their mobile device,” said Harriott. “When combined with these recent mobile open findings, the conclusion is clear: Small businesses must have a mobile-first mindset when it comes to their email marketing.”

Earlier this year, we looked at what various professionals from the industry think it takes to improve email open rates. You can read that here. Also check out this infographic running down ten tips for doing so.

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