Email has the potential to deliver a strong ROI for marketers, though the precise response rates depend on a number of factors including the subject line, type of offers and the time of day the email is sent.

Obviously the only way of accurately finding the optimal time of day to send your emails is to run tests, and you also need to take into account fluctuations around pay day and annual events such as Christmas and bank holidays.

There is even a way of running tests using Google Analytics, which we blogged a few years ago.

According to the Econsultancy/Adestra Email Marketing Industry Census 2013 only half of businesses (49%) are currently testing the time and day of their email messages, so either the other 51% already know the optimum time or they’re working off a hunch. 

So to give some food for thought on where to start testing, here are six case studies and infographics that look at the best time and day of the week to send emails…

Mail Chimp case study

  • Mail Chimp analysed more than a billion emails to identify trends in the optimal time to send marketing messages.
  • It found that email opens increased after 12pm, with the most active period being between 2pm and 5pm.
  • Tuesday and Thursday are the busiest days in terms of email volume, so it might be worth testing other days to help your messages stand out from the crowd. However, it might also be that these are the most successful days for a majority of marketers.
  • There is a noticeable drop off in the email open rate on weekends, so it’s probably best to avoid sending important messages on Saturday or Sunday.

eBags

Online retailer eBags managed to increase email clickthrough rates by 20% and conversions by 65% after running tests to find the best time of day to send out its marketing messages.

The company carried out research based on the hypothesis that if users were available to sign up to an email list at a certain time, then they would be far more receptive to receiving an email at the same time as when they signed up.

The best time to send the email was individually calculated by looking at the behaviour of each user, recording the exact time when they signed up to the list.

The results were:

  • Click-through rates increased by 20%.
  • Conversion rates increased by 65%.
  • Average value per order increased by 45%.
  • Overall average revenue per recipient increased by 187%.

But while the email campaign was incredibly effective, eBags did not employ this technique in all of its campaigns. 

Larry Martin, head of the programme, explained that sending out individually timed emails is both very time-consuming as well as technically difficult.

Get Response case study on the best day of the week

  • A study from Get Response analysed 21 million emails sent in the US during Q1 2012 – overall it supports the fact that the majority of inbox traffic and activity takes place during the working week, peaking on Thursday.
  • In fact Thursday was the top day for all metrics: percentage sent, open rates and CTR.
  • The open rate drops off slightly on the weekend, while the CTR drops off massively compared to the peak on Thursday.

Experian’s quarterly email benchmark study (AdWeek)

Best times to send email for opens and clicks (Get Response)

The best and worst times to send emails (pure360)