There are many research studies and tips for considering general best practice advice for emails. All great but NOW IGNORE IT!
There are many, many, situations which quickly challenge the classical suggestions. Another way to think about it is your audience is busy just like you and can't always take the time to read, let alone see in their overcrowded inboxes.
Your audience is the exact reason that the "Time the email is received" is so important!
I would suggest that for a subscribed newsletter create a consistent expectation that your reader will know when to look for your newsletter to arrive. Then promote that time and date consistently! For example, Sunday night is Newsletter "X" night!
Other "Email Time" things to consider are:
1. The Newsletters special interest – For entertainment, self-help, a productivity-related topic, work related? All are factors. Often you can reference Paid Search volumes, i.e. AdWords for most frequently searched for a source of insight!
2. Understanding your demographics - The single most important thing you can do for email newsletter success is know your audience. Some examples of how demographics override the safe “best time to send” general advice:
-The much-maligned Friday could be a great choice if you’re in the entertainment industry, with folks looking for fun things to do over the weekend.
-Weekends don’t have to be off-bounds either. What if you’re interested in reaching audiences in cold-weather climates? I bet they spend plenty of time checking emails on Saturday and Sunday.
-Mornings are great for introspective thoughts for your day.
-If you’re targeting the young, tech-obsessed crowd, you would probably ignore the general tip about not sending emails at night. Evening emails could work just fine for younger audiences.
3. Time zones and translations - You always want to customize email send times based on where your recipients live.
4. The Device - Traditional “best time to send an email” numbers are being thrown to the wind as user habits change across devices. The standard mid-week, mid-day makes perfect sense for desktop users who are opening emails at work. Mobile users, on the other hand, tend to be pretty active even late in the evening.
THE MORAL OF THIS STORY IS >>> A/B test your send times like crazy. This is the best way to find the perfect send time for your particular audience or even better send a survey!
FYI - Bad open rates aren’t just about your send times.
If your open rates aren’t looking so good, consider - Do You Have a Standout Subject Line? Subject lines are HUGE when it comes to email newsletter opens. You could argue that subject lines are even more important than the email content since it’s the subject lines’ job to get people opening your message, to begin with.