When Should Brands Send Marketing Emails? 26 Billion Emails Point to Tuesday for Opens and Friday for Sales

Omnisend, a leading ecommerce marketing company serving over 150,000 brands, analyzed 26 billion marketing emails to determine the best send days and times for driving opens, clicks, and sales. The analysis found that Tuesday is the strongest day for awareness campaigns, generating the highest weekly open rate of 31.27% and the highest click-to-sent rate of 0.81%.

However, campaigns focused on sales may want to look later in the week. According to the data, Friday generates the highest conversion rate at 0.081%, making it the strongest day for sales-driven campaigns.

Saturday was the weakest day in the analysis, posting the lowest click-to-sent rate at 0.68% and the lowest conversion rate at 0.058%. It also had the lowest send volume, with 3.14 billion emails sent, suggesting many brands already avoid weekend campaigns.

“The main takeaway is that there isn’t one perfect day to send every email,” says Marty Bauer, ecommerce expert at Omnisend. “Tuesday may be strongest for opens, but Friday performs better for conversions. Marketers should start with the outcome they want – visibility, clicks, or sales – and then choose send times based on that goal.”

Email Engagement Peaks Early in the Morning and Again in the Afternoon

The analysis also found that the hour of send can change campaign performance, not just the day. Across the week, two time periods stood out most consistently: early morning, when conversion and click activity were strongest, and mid-afternoon, when engagement rose again.

• Conversions performed best before the workday was fully underway: Friday at 7 AM had the highest conversion rate at 0.138%, followed by Monday at 8 AM at 0.114%.
• Clicks followed a similar early-day pattern: Click activity was strongest around 7–8 AM, with another lift at 4 PM.
• Opens peaked slightly later in the morning: The most reliable window for email opens was between 9 AM and 11 AM.

“A lot of brands still treat send time like a calendar choice, but it is really a customer behavior choice. Early morning appears to be when shoppers are more ready to act, while later morning is stronger for getting attention. That means marketers should stop asking only when people are most likely to open an email and start asking when they are most likely to do something with it,” says Marty Bauer, ecommerce expert at Omnisend.

What brands should do with this data

While Omnisend’s analysis shows patterns across billions of emails, Bauer says brands should treat these findings as a starting point rather than a universal rule. The best send time can vary depending on the audience, product category, time zone, purchase cycle, and whether the campaign is built for awareness, engagement, or sales.

He recommends marketers focus on five steps:

• Match the send time to the campaign goal. If the goal is visibility, open rates matter more. If the goal is revenue, click and conversion rates should carry more weight. The time that drives the most opens may not be the one that drives the most purchases.
• Test send times over several campaigns. Brands should test different send times across a series of campaigns before drawing conclusions. This helps identify patterns without relying on a single campaign, which can be influenced by the offer, subject line, audience size, or seasonality.
• Segment by audience behavior. Time zone, shopping habits, device usage, and lifecycle stage can all influence engagement. Marketers should compare results across segments instead of assuming one send time works for everyone.
• Test one variable at a time. When experimenting with send times, brands should keep the audience, email content, subject line, and offer as consistent as possible. This makes it easier to see whether timing influenced the result.
• Use marketing automation to act on customer behavior. Brands do not need to rely only on campaign timing. Automated emails and SMS, such as welcome messages, cart abandonment reminders, and post-purchase follow-ups, can be triggered by customer behavior, helping brands reach shoppers when they are already engaged.