How To Effectively Optimize Your Email Marketing Send Time




To know the best time to send emails, you need to optimize your email marketing campaign effectively. In today's article, I will discuss everything you need to know about send time optimization.

First, here's a little backstory.

In 1971, Ray Tomlinson invented and developed electronic mail when even the smallest computers needed a wheelbarrow to move. In those early days, computers were a device used for small tasks. Still, the Blackberry, iPhone, and Android introduction in the 2000s made our email inboxes very accessible.

Fast forward to 2021. Technology and our culture have evolved together through time. According to Zenith, the average time spent per user each day in the US on mobile internet devices is expected to jump to 4 hours and 30 minutes this year.

Best time to send email marketing - Mobile internet usage stats

Mobile devices have allowed us to bring our digital lives, our work, and our personal lives anywhere we go.

What does this mean for marketers and salespeople? It has helped us realize the importance of optimizing our send time to engage with people using email.

What Is Send Time Optimization?

According to Emarsys,

Send Time Optimization (STO) is an AI-driven add-on for your email campaigns, which analyzes the email responses of every recipient in relation to the campaign launch time, and then sends the next email at the optimal time for them.

Here's a simple diagram from Emarsys that shows how Send Time Optimization works:

Best time to send email marketing - STO diagram

Send Time Optimization (STO) increases the chances of your emails getting engagements from your audience. For your customers, it shows how you treat them as individuals. STO also strengthens brand loyalty and improves customer experience.

The Importance of Email Send Time Optimization

There are three main reasons why people usually unsubscribe from email lists: 

  • They receive too many emails. 
  • The permission subscribers gave you is not real.
  • They receive a lot of irrelevant content.

What does this mean to marketers? We need to do a great job of setting proper expectations when people subscribe to our lists and our content needs to be top notch.

The Different Levels Of Send Time Optimization

Send Time Optimization, aka STO, describes several different email timing optimization or personalization levels. Now let's break down these different levels from non-optimized to personalized.

1. The "Whenever" Blast

Email has grown exponentially despite the invention of new messaging apps and platforms like Messenger, Skype, and WhatsApp.

Creating an email is cheaper, instantaneous, and practically free.

The "Whenever" Blast is a convenient, unplanned, and unexpected type of email in the Send Time Optimization levels. It is also known as the “when I feel like it” email.

2. The "Best Guess" Blast

This one is the opposite of the "whenever" blast.

Remember that just because you can send an email whenever you want doesn't mean you should, even if it will be waiting in your customer's inbox.

As email marketers, business professionals, and salespeople, we need to remember that timing matters, especially when sending information like promos and other sales offers.

Sending an email in your recipient's inbox while they are in front of their computer or mobile devices can increase the chances of them reading your message.

Sending an email at the wrong time is risky, so many marketers have turned to trial and error or relied on studies about the best time to email.

The "Best Guess" Blast is the most basic Send Time Optimization form and probably still the most commonly used. At this level, you simply guess the best time when most people will be in front of their computers and then send an email.


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3. The "List Optimized" Blast

A "List Optimized" Blast is sent at a single optimized time based on data on the list's peak engagement time.

Discovering the best delivery time for an email list increases open rates, so focusing on finding the ideal email list send time is likely worth your effort.

Your email list may have people coming from different industries, which may skew your list's peak time to an unforeseen result. With so many email marketers now using "best guess" blasts, traditionally optimal times may change as inboxes reach fullness.

You can find the peak engagement time for a list through systematic A/B testing. Many email marketing service providers have features that allow you to automate this process to have list level Send Time Optimization within 24 hours.

Email list STO level combined with Timezone Sending is currently the highest STO level commonly used in the industry.

4. The "Timezone Optimized" Blast

You can use the timezone sending feature with the list level Send Time Optimization that many email marketing platforms offer.

Even if your email recipients' peak times were the same, you would still run into problems if there are no people within your home or target timezone.

If you have an international email list, whatever time you select, some of your recipients will receive your email at night time.

A "Timezone Optimized" Blast solves this problem by dividing your email list down by each user's estimated time zone and then sending your email at your preferred time in their timezone.

5. Personalized Delivery

Personalized Delivery is the highest standard of Send Time Optimization. It uses machine learning to allow you to make sure each individual receives your email when they are most likely to engage.

Depending on the email service provider, you can choose a time window between 12 hours up to 7 days. Each subscriber will receive your email at the optimal time.

Personalized delivery is an effective Send Time Optimization strategy. By profiling each subscriber on a list based on past email engagements like opens, clicks, device, etc., you can identify the optimized delivery time for each individual on both hourly and daily level based on this data.

Many companies have libraries of open and click data from years of communications with customers. An email personalization system can extract this existing data to build profiles that both sales and marketing teams can use.

Where To Use Automatic Email Send Time Optimization

Here are the different ways you can use Automatic Email Send Time Optimization for your business to boost engagement, conversion rate or meet email marketing goals: 

  • Sales outreach follow-up: Use for influencer outreach, schedule a call, and sell products or services.
  • Lead acquiring workflows: If a subscriber downloads a free ebook, send a Thank You message right away. But, in many cases, you need to follow up a few times.
  • Newsletter follow-ups according to behavior like link clicks.
  • Lead nurturing by sending out informative content.
  • For webinar, service, or product promotion.
  • Retargeting email campaign to win a customer back.
  • User onboarding email series.
  • All types of sales: upsell, cross-sell, upgrades, etc.

And that's how to optimize your email marketing send time effectively!

Check out the recommended resources section below to learn more about Send Time Optimization. 

Recommended LinkedIn Ads Resources

The Best Time to Send Emails to Boost Opens, Clicks, and Sales

How To Catapult Your Email Campaign Optimization To The Next Level

Case Study: Increase Email Engagement Utilizing Send Time Optimization

So what do you think about this article? Are you ready to optimize your email marketing send time?

Leave a comment below, and let's chat.

As always, it will be a huge honor if you think this article is worth the SHARE!


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Header image courtesy of Pixelied.

About the author, Tim Fitzpatrick

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