Take Your Open Rates to the Next Level with Smart Send Time

We’ve all been there before. Your email campaign is ready to send. You’ve perfected the content and copy, You’ve matched it to your segmented audience. Then the final challenge occurs to youwhen is the best time to send this email to get the most people to open it? 

Last year, Klaviyo’s Smart Send Time feature solved this challenge. Smart Send Time uses a custom-developed optimization technique to learn the behaviors of your email recipients and tell you exactly when to send messages to maximize your open rates. But in conversations with customers, it became apparent marketers wanted additional flexibility to maximize the effectiveness of Smart Send Time.

So, we listened. Smart Send Time is now more versatile and more useful with options to identify a Smart Send Time for multiple unique audiences. Let’s find out what’s now possible. 

More options for testing and sending

Previously, the sequence of tests needed to get a Smart Send Time for your account was

  1. Send an exploratory send to at least 12,000 recipients across a 24-hour window
  2. Send “focused sends” in a four-hour window centered on the optimal send time
  3. Send from your determined optimal send time 

Once an optimal send time was established, you could use it to send any future email. Then, Klaviyo automatically used a four-hour window around your optimal send time to keep collecting engagement data. 

For example, if your optimal time was 12 PM, then Klaviyo would send some emails between 10 AM -12 PM and some between 12-2 PM to continue to learn from customer engagement behavior. This way, if customers start opening earlier or later, Klaviyo can automatically adjust the sending time.  

Despite the power of this feature to increase your open rates, Smart Send Time needed to be used in this specific way and could only be used once. Starting today, Smart Send Time is more flexible and more powerful. You can now choose to: 

  1. Run multiple Smart Send Time tests, which means sending multiple exploratory sends to different audiences.
  2. Keep sending exploratory messages over a 24-hour span. This allows Smart Send Time to continue gathering open rate data while sending outside your Focused Send window.
  3. Send directly at your Optimal Send Time without the four-hour window. This is an easy way to send an email at your best time, in one click. This option lets you send a campaign to 100 percent of your recipients at your optimal send time and won’t gather more engagement data.

Multiple Smart Send Times for each account 

Yes, you read that right. You can have more than one Smart Send Time in your account! 

What does this mean? As long as you have enough recipients to run an exploratory send (12,000+), you can find out what your optimal sending times are for different segments of customers or even days of the week. 

For example, maybe the best time to email your newsletter list is 10 AM, but your VIPs are more likely to engage at 7 PM. Maybe Tuesday you should send your campaigns to your main list at 11 AM, but if you send it on a Thursday, you should send it at 6 PM. 

Now, you can create those tests and find out

  1. Re-test your original Smart Send Time test from the Exploratory phase without losing the original test’s learnings.
  2. Measure whether there’s a difference in ideal send time (by way of highest open rate percentage) for recipients who click on your messages versus recipients who open your emails but don’t click.
  3. Test optimal send times by season and/or by seasonal product line.
  4. Test optimal send times by campaign type. For instance, test whether your newsletter campaigns have a different optimal send time than your sale campaigns.


Results that are easier to understand

After you’ve sent one or more Smart Send Time campaigns or tests, you can view your results on the Smart Send Time Report page. This page is accessible via the “Options” dropdown on the Campaigns tab.  

For any Smart Send Time test, you can view all of the underlying data. You can see:

  • Open rates by hour for exploratory sends – shows you how Klaviyo selected your Smart Send Time
  • Open rate lift – tells you the increase in open rate when sending at your original Smart Send Time compared to the open rate data of your exploratory sends
  • The Activity Timeline – shows a timeline view of all campaigns sent in a given experiment. It includes when a campaign was scheduled, canceled, and started sending as well as its send type (exploratory, focused, optimal, etc), when the campaign’s data was analyzed (attributed), and whenever a smart send time changes for the test

Additionally, if you’ve run multiple Smart Send Time tests you can view and compare the data for each test. If those tests targeted the same segment of customer, you can look at the underlying data and compare the hour open rates to more fully understand how your Smart Send Time was formed. 

Looking at your results may inspire you to test something newa new day of the week, a new audience subgroup, or a new type of campaign. 

If you do get inspired, you can start a new test from the reporting page. Simply click “Create New Test” to open up a modal where you can name your new test and add any notes to remind yourself about what the test is and why you tested it for future reference.

Learning the best time to send your emails has never been easier. These updates to Smart Send Time allow you to run tests on eligible groups of subscribers and pinpoint the right time of day to send their next campaign. 

If you have a group of at least 12,000 recipients, start a new Smart Send Time test today! 

Need more subscribers to be eligible for Smart Send Time? Learn how Klaviyo Signup Forms can help grow your marketing list.

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