Emails sent in the morning result in the highest open rates, reports Informz [download page], which based its finding on an analysis of metrics collected from more than 600 million emails sent by over 700 large and mid-sized associations that used its email marketing platform in 2011. Morning emails saw an average open rate of 39.2%, ahead of those sent at midday (33.9%), in the late afternoon (32.1%), and at night (32%). However, emails sent in the morning had the lowest click rate (16.5%), behind ones sent at night (18.6%), at midday (19.7%), and in the late afternoon (21%).
This finding conflicts with September 2011 research from Pure360, which indicated that the best time to send marketing emails to consumers is between 7 and 10 PM.
Data from Informz’s “2012 Association Email Marketing Benchmark Report” indicates that email open and click rates did not vary significantly based on the day of week sent. Open rates ranged from a low of 32.77% on Tuesdays to a high of 35.19% on Fridays, while click rates saw a low of 18.52% on Mondays and a high of 19.85% on Wednesdays. The report also notes that delivery rates did not change based on the day of the week sent.
The average metrics for associations included a 98.28% delivery rate, 34.33% open rate, 19.49% click rate and 0.052% unsubscribe rate.
The length of email subject lines did have a significant effect on open rates, though. Subject lines less than 10 characters long boasted an open rate of 58%, 38% higher than the next-highest open rate, for subject lines of 50-59 characters in length (42%). Subject lines between 10 and 50 characters long saw an open rate of roughly 35%, while rates dropped to 31% for subject lines of 60-69 characters, and 28% for those even longer.