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send time optimization

Every marketer, at one time or another, has wondered when the perfect time to send emails is. Are recipients more likely to open messages in the morning or late at night? What about on Tuesdays at the lunchtime hour?

The problem is, there’s no single “best” time to send an email. There are too many variables and assuming that a specific day and time will always get you the most opens is ridiculous. But thankfully, due to technology and a handy feature called send time optimization, marketers no longer have to fret about when to send their emails.

In this blog post, we’ll discuss what send time optimization is and why it’s important. Then we’ll look at eight different vendors who offer this feature and how they do it. Sound like a plan? Great, let’s get started!

What is Send Time Optimization?

First things first, what is send time optimization? In a nutshell, it’s a feature in some email marketing platforms that analyzes when a recipient is most likely to open an email. The platform then sends messages at that time.

For example, let’s say you want to send an email to Sally. It’s a really important message and you want to make sure she not only sees it but also opens and reads it. So you go into your email marketing platform of choice and power on the send time optimization feature.

Now, once you hit send, your email service will analyze the data it has on Sally and determine which day and time she is most likely to open your message. In this hypothetical scenario, Thursday evening at 7:11 pm EST is the sweet spot.

A feature like this has value. It allows you to increase open rates and better engage with subscribers — both of which lead to more profits for your business.

8 Vendors With Send Time Optimization

Now that we know what send time optimization is and why it’s valuable, let’s talk about the vendors who offer it. Each of the eight companies listed below will allow you to optimize email send times in some way. Below, we’ll dig into how each vendor achieves this.

1. Robly

Okay, we have to toot our own horn for just a second. At Robly, our send time optimization feature is powered by our patent-pending AI technology. It’s easy to use, and delivers an entire campaign to each person individually at the best prescribed time. The feature is included at all plan levels.

Simply log in to your account and navigate to the campaign builder. Once your email has been written and designed to your liking, you’ll have the option to enable Robly AI. Toggle it on and select a sending window, which determines the maximum amount of hours you’re willing to wait to have your email sent to subscribers.

Once you’ve sent the campaign, Robly AI automatically evaluates the data regarding each of your subscriber’s open habits. It will then send your email to each individual subscriber at the time they are most likely to engage with it.

Robly’s send optimization features works on an individual subscriber level. The more you use it, the more data points it can collect, and the better it will work. Whereas other platforms may send your emails at a single time that works best for your entire list, Robly sends individual messages at the perfect time for each recipient. This ensures an incredibly high open rate for our users.

2. MailChimp

MailChimp is another email marketing platform with send time optimization capabilities. It should be noted, though, that this feature is only available via paid plans starting at $15 a month or more depending on subscriber count.

To power its send optimization technology, Mailchimp constantly collects and analyzes data from its massive user base. This data is used to pinpoint ideal send times for each individual contact. Messages are then emailed at the predicted best time for every subscriber.

The Send Time Optimization feature is very easy to use. Users simply hit the “schedule” button once their campaign has been crafted to their liking. They then select the “Let Mailchimp optimize send time for maximum engagement” and, voila, Mailchimp’s send time optimization feature is activated.

3. SendinBlue

SendinBlue is an email marketing platform headquartered in Paris, France. It’s send time optimization features is available to customers of its premium, premium+, and enterprise plans which start at $66 a month or more.

To enable this feature, users draft a campaign as they normally would. On the scheduling step, there are three options: “Send it now,” “Schedule it for a specific time,” and “Send it at the best time.” Users should select the third option and choose a specific date for the campaign.

Once a date has been chosen and the “Confirm” button clicked, SendinBlue will send the email campaign on the designated day, at the optimal time for each recipient. Because SendinBlue’s Send Time Optimization feature sends emails at the ideal time for each individual subscriber (like Robly and Mailchimp), it has a much better chance of increasing open rates than a platform that simply bulk sends messages all at once.

4. Campaign Monitor

Campaign Monitor offers send time optimization to its “premier” level customers. The premier plan is the company’s most feature-packed offering. It’s also its most expensive starting at $149 a month. Fortunately, that bundle of cash does get you a send time optimization tool that works on an individual subscriber basis.

Campaign Monitor understands that the time an email is sent is just as important as the subject line, content, and call-to-action included with the message. So back in 2017, the email provider added the send time optimization feature, which analyzes every individual subscriber’s previous engagement (ie, clicks and opens) with your brand. It then chooses the perfect send time based on this data and emails messages to people when each is most likely to open it.

5. GetResponse

GetResponse is a very popular marketing platform. Beyond just email, the service also gives users the ability to create landing pages and webinars. But what about send time optimization? GetResponse claims its version can increase opens by 23%.

Like each of the solutions already mentioned, GetResponse’s send time optimization featured (named Perfect Timing) works on an individual subscriber basis. Perfect Timing uses billions of data points to create subscriber profiles inside its system. It then uses this information to predict the time every email subscriber on a list is most likely to engage with a message and sends it then.

Perfect Timing is available to all GetResponse users. After a 30 day free trial, plans start at $15 a month or more depending on the number of subscribers a user has and the features he or she wants access to.

6. ActiveCampaign

ActiveCampaign has invested heavily in machine learning and this commitment has led them to develop a send time optimization feature which they call Predictive Sending. All users have to do is check a box while crafting their messages and ActiveCampaign will send their emails at the optimal time, based on the data it’s collected and stored for each subscriber.

According to their website, “Our data model will rank each hour in a day based on a contact’s habitual open time, and ActiveCampaign will use these recommendations to schedule an appropriate send time.”

Because the ActiveCampaign “brain” is always learning, the more often that users send emails, the “smarter” the software gets. In theory, the 100th email a user sends should have a more precise send time than the first and open rates should be higher.

While Predictive Sending is a handy feature, it’s only available to those on either a professional or enterprise plan, which start at $129 a month when paid yearly.

7. Sendlane

Sendlane’s send time optimization feature works similarly to most of the others we’ve reviewed so far. Through Beacon, the name of the enhanced behavior tracker that monitors subscriber actions on multiple fronts, Sendlane is able to send messages to each subscriber exactly when they are most likely to open them.

To use this feature, Sendlane users simply create campaigns as they normally would. They can then initiate “Machine Learning Open Predictability” on the scheduling page. Once the campaign is confirmed, Sendlane will mail it at the optimal time for each recipient.

Beacon and the Machine Learning Open Predictability feature is available to all Sendlane users. Plans range from $35 a month to more than $300 depending on the number of subscribers the user has.

8. Infusionsoft

Finally, we have Infusionsoft. This provider takes a different approach to send time optimization than the other tools we’ve already mentioned. Rather than sending individual messages at the perfect time for each subscriber on an email list, Infusionsoft sends all messages at the average best time for the list as a whole.

Just like with every other platform already mentioned, enabling Infusionsoft’s send time optimization feature is a one-click deal. After a user has created a campaign and chosen the “Review and Send” button, they’ll be given the opportunity to select “Send at best time today.”

Making the Most of Send Time Optimization

Most of the solutions on this list operate similarly when it comes to send time optimization. Which platform you choose, then, will really come down to three things:

  1. Accuracy: Which tool will consistently get your emails in front of subscribers at the ideal time? This may be difficult to determine without using each service for yourself. We recommend reading reviews to find answers.
  2. Price: While each service on this list offers send time optimization, the prices between provider can vary drastically. Make sure you choose a solution that fits your company’s budget. Fortunately, multiple options are available for as low as $15 a month.
  3. User-Friendliness: Lastly, consider the user-friendliness of the entire platform. Each service reviewed makes it very easy to enable its send time optimization feature. But you’ll be using your platform of choice to do more than toggle specific features on and off. Choose an email provider that you enjoy using.

There you have it. You now know what send time optimization is, why it’s important, and eight vendors who offer this feature. Not sure where to start? Take one of our free trials for a spin to test drive our RoblyAI feature.

Jacob Thomas is a freelance copywriter and content marketer based in Nashville, TN. His professional writing approach has helped numerous businesses gain more traffic, leads, and sales. To contact Jacob, visit

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