People around the world send approximately 281.1 billion emails every day.

Amid all of that noise, how can businesses break through their employees' inbox overload and create messages that people actually want to read? To answer that question, my company, PoliteMail, analyzed anonymous data from nearly 200 million internal email communications and evaluated things like recipient attention and engagement rates.

Are you wondering how often to email your workforce, what content length works best, whether to use images or what time of day is best for sending a broadcast email? Here are six insights, backed by our benchmark data, that can help you improve internal email communications.

What Is the Ideal Length of an Internal Email?

If you’re wondering how long your internal emails should be, the answer is simple: Think short. Get to the point, and keep the content focused.

The best readership metrics result from messages that take two minutes or less to read. That’s 400 to 500 words, and the metrics really start to decline for messages that are 750 to 800 words long. When an email takes two minutes or less to read, about 40 percent of employees read an average of 82 percent of the content. For every 1,000 words you add, expect your readership to drop by 10 percent. 

The same goes for your subject line. Short subject lines — those with fewer than five words — perform best. 

Successful organizations have busy employees. Don’t demand too much of their time by sending dense, content-heavy messages.

How Often Should You Send Broadcast Emails?

When it comes to the frequency of your enterprisewide emails, our research shows that broadcast messages that are sent at a rate of once a week yield the best open, read and click rates. That frequency rate may be higher than you expected, but the key is to send short emails that are easy to read.

Email overload is less about the volume of emails and more about the relevance and length of the messages. Think about how it feels to receive a lengthy email. “I don’t have time to read this right now” is a common reaction, and that leads to a lower attention rate, because employees often close long emails and forget to circle back to them.

Related Article: Why Email Still Lingers in the Collaboration Tool Mix

What’s the Best Time to Send?

Send emails early in the day, and establish a routine schedule.

Emails sent early in the morning — and early in the week — achieve better engagement metrics than those sent later in the day and later in the week.

If your message is near the top of the employees’ inboxes when they get to work on a Monday or Tuesday morning, you’re more likely to get attention and readership. Don’t wait until Thursday or Friday afternoon.

You can also improve readership and engagement by establishing a consistent schedule. When employees receive an email at a regular time on a regular day, the data shows an increase in attention, as well as higher readership and click-through rates.

What Does a Successful Email Message Look Like?

The messages that perform the best are either all text or mostly images (those in which more than 50 percent of the message content is image area). 

Learning Opportunities

Eye-grabbing images and graphics increase readership and engagement. The greater the image-to-text ratio, the higher your email readership. 

In fact, messages that are mostly images have 17 percent higher readership than messages that are mostly text. Images like infographics and photos are easy for readers to digest. Likewise, image-heavy messages are more likely to attract a reader’s attention than those with large blocks of text.

Related Article: Avoiding Employee Burnout in the Always-On Workplace

How Can You Increase Readership Rates?

If you want to increase your readership rates, segment your audience. 

Our research yielded this finding: The larger the audience, the lower the results. Before you send an email, consider whether everyone in the organization really needs to receive it. The average ignore rate is lowest when you send a message to less than 1,000 recipients and highest when you send an email to 25,000 to 30,000 people.

If you want to grab your employees’ attention, segment your audience and choose the recipients of certain messages based on employees’ attributes or behaviors.

Which Email Metrics Matter Most?

While it’s interesting to know what percentage of recipients open your emails, an email open rate is really only an indication of your reach. Based on the results of our research, the average unique email open rate across all industries is just over 71 percent, but nearly 10 percent of those recipients actually ignore the email. This means they open the message but view it for less than three seconds. 

Metrics that do a better job of determining message effectiveness are attention rate, readership, reading percentage and click-through rates. Those metrics tell you more about recipient engagement than open rate, and they offer much more valuable and actionable insights. After all, the intent of sending messages is to get employees to read them.

Just as companies compare their business and financial performances with those of their peers, in order to assess the effectiveness of your internal email communications, you need to gather your own email metrics and compare your results to industry benchmark data. But even without measurement data, you can send better, more effective emails by creating short, easy-to-read messages with eye-catching images and sending them early in the workday.

Sending more effective emails doesn't have to be guesswork. Measuring email performance and using the data to understand which emails resonate best with your internal audience can help you gain the attention of employees while increasing readership.

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