What is the Best Day to Send Email?

Oh no, not again. Does everyone hear that rumbling sound? It’s the noise 1,000 marketers make when they rush to change the day they send email based on a new study (this time from eROI). And at the already-busy Christmas season at that.

We can’t say it enough: the best day to send email is the day that your email performs the best. How do you know when that is? Test it, test it, test. And then, test it again. Sorry, there is not fast route to optimized email results.

But meanwhile we wanted to highlight another tidbit of information in this study: that large lists see lower response. We aren’t surprised by this. Why? Because larger lists are also older lists. The lower response is due to what we call the “inactive rate” – the percentage of subscribers who do not open, click or convert in 3 or 6 months. We’ve been recommending that clients pay attention to retention from the very first email and then pull inactives every three months and embark on recapture campaigns. It’s really hard to reconnect with someone who has tuned out your email and the longer you wait to try it, the less success you’ll have.

While not universally true, bigger lists also tend to be more diverse than smaller lists. Being all things to all people rarely works in marketing except for really big consumer brands (and maybe not even then, actually). Did someone say targeting and segmentation? Sending specific messages to smaller groups is generally going to yield higher revenue per email than sending one message to a whole bunch of people.

Of course, this is a big generalization. The caveat is that it’s not the size that matters but the make-up of the list. It is possible to have a 1,000,000 people that all fit into a single niche or to have 3,000 people who don’t have anything in common. That also fits with the point about age, since you can have a big list that is fresh and a small list that is old. So it makes sense then, that an aggregated study would find these trends to be true, but that doesn’t help an individual marketer make decisions about their email if their list doesn’t match these averages.

Getting comfortable with testing and analyzing your metrics is going to yield far better results than jumping on the “study of the month” bandwagon hoping for a quick fix.

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