What Time Should You Send Emails? A/B Testing Guide

Getting your marketing emails opened—and acted on—depends on more than just your content or your subject line. The timing of your emails is a critical factor that can make the difference between being read, ignored, or deleted. For small businesses trying to reach their audience effectively, knowing when to send emails is both science and strategy. While there are plenty of “rules of thumb” out there, the best way to find out what works for your audience is A/B testing.

Why Timing Matters in Email Marketing

With most business inboxes flooded each day, to compete for your subscribers’ attention you need to send your message when they’re most likely to see—and engage with—it. Here’s why email timing is important:

• Inbox Competition: If your email arrives at a crowded period, it may get buried under newer messages before your recipient checks their inbox.
• User Behavior: People’s routines (work hours, commutes, lunch breaks) strongly affect when they catch up on emails.
• Device Habits: The growth of mobile email means behavior has shifted—many check emails throughout the day, not just in the morning.

Sending at the wrong time can lead to lower open rates, click rates, and ultimately, fewer conversions.

Common Myths and General Recommendations

It’s tempting to lean on industry averages or “best times to send” lists found online. You’ll often see advice like:

• Send emails on Tuesdays or Thursdays at 10am
• Avoid sending on weekends
• Early mornings or right after lunch are best

However, these recommendations are based on broad trends, not your specific subscribers. Factors such as your industry, the geographic location of your audience, their age, occupation, and the nature of your emails all play a role. No universal best time fits every audience.

What is A/B Testing for Email Send Times?

A/B testing—also known as split testing—is a method where you send versions of an email at different times to similar segments of your list. By comparing their performance, you learn which time yields better results, allowing you to refine your strategy based on real data, not guesswork.

How Does it Work?

You divide your subscribers into at least two groups, then send the same email at different times to each group. You then measure key metrics, such as:

• Open rates
• Click-through rates
• Conversion rates
• Unsubscribe or complaint rates

The group whose metrics outperform the others indicates a preferable send time for your audience.

Step-by-Step: How to A/B Test Email Send Times

1. Define Your Objective

What are you hoping to learn or improve? Is it maximizing open rates, clicks, website visits, or sales? Your objective determines which metrics matter most.

2. Segment Your Audience

Randomly divide your email list into equal-sized groups. Larger lists yield more reliable data—ideally, several hundred recipients per test group. Avoid overlap between groups to keep results valid.

3. Select Test Times

Choose the send times you want to test. Start with two options (A and B). For instance, try 8am vs 1pm. You could base these on:

• Your own hypotheses (e.g., “Are my subscribers morning readers?”)
• Previous email performance from your analytics
• Industry benchmarks, adapted to your business

4. Create Your Email

Use the same subject line, content, and sender information for each group. This keeps the only variable as the send time.

5. Send & Measure

Send your email at the scheduled test times to each group. After a set period (e.g., 24–48 hours), review your results in your email marketing platform.

6. Analyze Results

Focus on your primary metric (e.g., open rate or click rate). Is there a clear winner? If the results are very close, you may need to repeat the test or try more distinct times.

7. Iterate and Refine

Continue testing over multiple campaigns to ensure your results are consistent. You may wish to try different days of the week, or test new hypotheses (e.g., early mornings vs late afternoons).

Tips for Effective A/B Testing of Send Times

• Test One Variable at a Time: Changing both subject line and send time in the same test will leave you guessing which factor influenced your results.
• Use Sufficient Sample Size: Small groups can yield misleading outcomes due to variance. Try to involve as many real subscribers as possible in each test.
• Measure Over Different Days: Test weekdays versus weekends—don’t assume your audience behaves the same every day.
• Consider Time Zones: If your audience is geographically dispersed, segment by local time zones for more accurate insights.
• Monitor for Seasonal Changes: People’s routines change during holidays, busy seasons, or major events. Retest periodically.
• Allow for a Response Window: Give recipients enough time to open and act on your email before judging results—at least 24–48 hours.

Interpreting Results and Acting on Insights

A/B testing will often highlight a “winner”—a time when more people open or click your emails. However, results should be treated as part of a broader learning process:

• Look for Patterns: Over several campaigns, do certain times consistently win? Or are results mixed?
• Combine Metrics: Sometimes you’ll see higher opens at one time, but better clicks or sales at another. Choose the send time that aligns with your main business goal.
• Watch Long-term Trends: Test regularly—what works today may shift as your audience’s habits or demographics change.

Beyond A/B Testing: Advanced Send Time Optimisation

Once you’ve built up data and reached a level of maturity in your email marketing, you might explore automations and advanced techniques:

• Send Time Personalization: Some platforms can send each email at the optimal time for each recipient, based on their past open behaviors.
• Triggered Emails: Set up automations that send emails when certain events occur (user signs up, abandons cart, etc.), making timing even more relevant.
• Dynamic Segmentation: Group subscribers by engagement, purchase history, or location, and test times within each segment separately.

When Not to Overthink Send Times

While optimizing email timing can boost results, don’t let it overshadow what matters most:

• Quality Content: An email with helpful, relevant content will outperform any cleverly timed but uninteresting message.
• List Hygiene: Regularly clean your email list to remove inactive or invalid addresses, which can hurt deliverability and skew test results.

If you only send occasional emails or have a small list, focus first on creating strong, valuable messages. For regular campaigns or newsletters, A/B testing your send times can make incremental but valuable improvements.

Key Takeaways

• Email send timing matters, but there’s no universal “perfect” time—your audience is unique.
• Use A/B testing to compare performance between different send times, measuring key metrics like open or click rates.
• Consistently re-test as audience habits, seasons, or industry norms change over time.
• Keep the process simple: test one variable at a time, use a sufficient sample size, and iterate on your findings for continuous improvement.

By making data-driven decisions about when you send your emails, you stand a much better chance of reaching your audience when it matters most—boosting engagement and achieving your business goals.

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