Reach shoppers when they’re ready to buy with personalized send time

In ecommerce, a few minutes can be the difference between a record-breaking sale and a buried notification.

We’ve all seen the traditional “batch and blast” approach: you hit send at 10:00 AM ET, and your message lands in tens of thousands of inboxes simultaneously. Some people see it immediately. But for many others, your message is quickly buried under a mountain of newsletters, work emails, and shipping updates by the time they actually check their phones.

The reality is that your customers don’t shop in sync. One subscriber might browse during their morning commute, while another doesn’t open a single app until they’ve tucked the kids into bed at 9:14 PM.

If you’re sending to everyone at the same time, you’re targeting when an “average” person is engaged. In today’s noisy world, “average” doesn’t cut it anymore.

That’s why we launched personalized send time, an AI-driven feature designed to help your messages reach the top of the inbox exactly when each individual is most likely to open, click, and convert.

What is personalized send time?

Personalized send time moves away from the “one size fits all” schedule. Instead, it uses AI models to determine when a recipient is most likely to engage based on their past behavior and similar profiles, and learns every time a new action is taken. 

With personalized send time, your messages will reach every individual when they’re most likely to convert. 

• Drive more sales with the right timing: Tailor send times on a 1:1 basis, predicting when each person is most likely to open, click, and convert.
• Fine-tune every channel: AI models calculate the perfect time for every send, whether you use email, text, push, or WhatsApp.
• Optimize on autopilot: Continuously learns and adapts to user behavior so you get better results without extra work.
• Implement with a single click: Just toggle on when scheduling campaigns. Quiet hours and local time are already included.

Why timing matters for your bottom line

The goal isn’t just open rates. Klaviyo’s personalized send time model drives revenue by automatically optimizing for opens, clicks, and conversions.

During our beta, top performing campaigns saw a 35% increase in click rates.* Every campaign sent with personalized send time is automatically tested with a control group to directly compare performance, and while performance can vary by business, you’ll be able to easily track your performance in Klaviyo reporting. 

“We used personalized send times for non–time-sensitive campaigns to reach subscribers when they were most likely to engage (and not get lost in the inbox abyss),” said Noele Crooks, Director of Consumer Retention & Analytics at the premium sunglasses brand Shady Rays. 

“It removed the guesswork from scheduling, saved our team time, and helped our messages land at just the right moment for our customers.” 

Shady Rays saw an over 10% increase in placed order rates after testing personalized send time with over 30 email campaigns. 

When to use personalized send time

While it’s always a good idea to tailor your communications based on customer behavior, personalized send time works best when you’re sending non-urgent campaigns. This means the overall performance is more important than getting a specific message out to your entire audience at the exact same moment. 

How do I use personalized send time?

Using personalized send time in Klaviyo is easy: 

1. When you schedule a campaign, select a sending window and turn on personalized send time. 
2. Klaviyo determines an optimal send time for each recipient of the campaign based on their past engagement on the channel, within your sending window and SMS quiet hours. 
3. Klaviyo will automatically create a control group and finish delivering messages. 
4. You can track the impact and performance lift from personalized send time directly in your campaign reporting. 

Personalized send time is now exclusively available as part of Klaviyo’s Marketing Analytics and Advanced Klaviyo Data Platform packages, which turns customer data into actionable automations.

Learn more about using personalized send time in your next campaign.

*Based on average click rate for the top 15% of campaigns sent using personalized send time from October to November 2025 when comparing the click rates of messages sent at personalized times with a control group of messages sent at a set time within each of those campaigns. Performance results are not guaranteed and may vary based on implementation, industry, and business model.