We have some data and insights to share with you regarding the when question.

TL;DR: The only way to truly know the very best time and day to send your emails is through a/b testing and deeply understanding your subscriber audience.

In the absence of test results, look elsewhere — to competitors, inspirational companies or entire verticals — to see when emails are sent. Allow that information to inform your specific strategies.

The best send time depends on the subscriber and the perceived context within which they might be receiving a mailer. For instance, our (customer only) data shows that e-commerce companies skew heavily for mid-day.

ecommerce send-time distribution

One might infer that online shopping happens most during the afternoon, so deals start flying at that time. Or, if the company is an “old-school” retailer, mid-day deals may encourage us to stop-off at the brick-and-mortar shop on our way home from work.

Meanwhile, news & media is less clear — basically anytime someone is awake seems to be fair game.

news and media send-time distribution

Why’s that? Well, different audiences consume content at different times. We have personal contacts at a few media companies and know qualitatively that they love to target mornings over the weekend. Perhaps to brighten up Saturday or Sunday, when email frequency is lowest.

Send time also affects how you design and code your emails.

On the aggregate, about a quarter of emails are mobile optimized, but what’s really important is looking on the more granular level. If you know someone is going to be waking up and reading email on their phone, it darn-well better be mobile optimized. If you’re a MailCharts customer, take a look at which companies are sending in the early mornings and their mobile optimization rate.

Personalization matters.

There are ESPs that provide personalized send times based on readers’ habits — when they open or click. Rather than sending at a fixed time, emails can be personalized based on unique data for each individual subscriber.

As for me, non-essential emails I receive between 12 noon and 5 p.m. get marked read without opening, or deleted.

Personally, I’m a bit of a high-strung guy, so once the day gets started, the noise of yet another email in my inbox must be quieted immediately! Mornings and evenings, as well as weekends, are the best times to reach me.

After all, it really depends on your specific subscriber list: who they are and how they respond to your mailers.

Feedback, thoughts, or otherwise? Let me know!