I always thought the best day to send out an email newsletter was Tuesday but I am changing my mind.  

What I had not considered until recently is sending an email newsletter on a Saturday.  A couple of our clients send their newsletters on a Saturday and it got me thinking.  

Doug Mackay Collingwood Search tried sending his newsletter out on a Saturday and found that not only did he get a higher click rate (by 10%) but also a longer tail - ie his newsletter usually got opened on the day it was sent but his Saturday newsletter was opened Saturday, Sunday, Monday and even Tuesday.

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Another client Fintech Collective always send out on a Saturday morning and get an amazing response. Their logic is that their audience is most likely to read their email newsletter on their mobile phone.  The newsletter is sent at exactly the same time every Saturday and it has become a routine for their audience to read the latest on Fintech over their morning coffee or whilst watching the kids play sport.

This is not at all scientific and a very very small sample but I think that mobile devices are key here.  If your newsletter looks good on a mobile, is relatively digestible then give Saturday a go.