Email Send Time Optimization: Best Times

When you send an email matters almost as much as what you send. The same email can see dramatically different results depending on when it lands in the inbox. This guide covers everything you need to know about email timing—from industry benchmarks to testing strategies that find your unique optimal send times.

Why Email Timing Matters

Understanding the impact of when you hit send.

The Inbox Competition

The Reality:

• Average professional receives 121+ emails daily
• Emails compete for limited attention
• First emails seen often get priority
• Poor timing means buried emails

Timing Impact: Well-timed emails can see 20-30% higher open rates than poorly timed ones.

What Timing Affects

Open Rates: Emails sent when recipients are checking their inbox get opened more.

Click Rates: Engaged readers at optimal times click more.

Conversions: Better engagement at the right time leads to more conversions.

Unsubscribes: Poorly timed emails (especially too many) drive unsubscribes.

The Timing Variables

Day of Week: Which days see highest engagement?

Time of Day: Morning, afternoon, or evening?

Time Zone: Your time or the recipient's?

Frequency: How often is optimal?

Email Type: Different emails need different timing.

General Email Timing Benchmarks

What the data says across industries.

Best Days to Send Email

Research Consensus:

Key Insight: Tuesday, Wednesday, and Thursday consistently outperform other days across most industries.

Best Times to Send Email

Research Consensus:

Time Windows:

• Morning Peak: 9-11 AM
• Afternoon Peak: 1-3 PM
• Evening Peak: 6-8 PM

Important Caveats

Benchmarks Are Starting Points:

• Your audience may differ significantly
• Industry patterns vary
• Test to find YOUR optimal times
• Benchmarks are averages, not guarantees

Data Sources Vary: Different studies show different "best" times. The truth is: it depends on your specific audience.

Timing by Audience Type

Different audiences have different patterns.

B2B Email Timing

Professional Audience Behavior:

• Check email during work hours
• Morning check before meetings
• Post-lunch catch-up
• Less engagement outside work hours

B2B Best Times:

• Best Days: Tuesday-Thursday
• Best Times: 10 AM, 2 PM
• Avoid: Weekends, early morning, late evening

B2B Considerations:

• Time zone matters (business hours)
• Industry affects patterns (finance vs. creative)
• Seniority affects schedule (executives check less often)

B2C Email Timing

Consumer Behavior:

• Check email throughout day
• Personal email on personal time
• Mobile checking increases flexibility
• Evenings and weekends viable

B2C Best Times:

• Best Days: Varies by audience
• Best Times: 10 AM, 8 PM
• Weekend: Can work well for leisure/retail

B2C Considerations:

• Demographics affect patterns
• Product type matters (impulse vs. considered)
• Lifestyle factors (parents vs. singles)

Mobile-Primary Audiences

Mobile Checking Patterns:

• Throughout the day
• Commute times (8-9 AM, 5-7 PM)
• Lunch break
• Evening browsing

Mobile Considerations:

• Subject line visibility limited
• Quick scanning behavior
• Location and context vary

Timing by Email Type

Different emails deserve different timing.

Promotional Emails

Goal: Drive immediate action (purchase, signup)

Best Timing:

• Before payday: End of month
• During high-intent times: Lunch, evening
• Sales: Tuesday-Thursday typically

Avoid:

• Early morning (too early for purchase decisions)
• Late night (unless time-zone specific)

Newsletter/Content Emails

Goal: Get read and engaged with

Best Timing:

• When readers have time to read
• Morning commute (mobile readers)
• Lunch break
• Evening relaxation

Consider:

• Match complexity to time available
• Long content needs dedicated reading time
• Quick updates can work anytime

Transactional Emails

Goal: Deliver expected information

Best Timing:

• Immediately after trigger
• No delay for order confirmations
• Real-time for alerts and notifications

Note: Transactional emails should be instant—timing optimization doesn't apply.

Welcome Emails

Goal: Start relationship strong

Best Timing:

• Immediately after signup (first email)
• Follow-ups can be timed strategically
• Consider onboarding sequence pacing

Re-engagement Emails

Goal: Win back attention

Best Timing:

• Try different times than regular sends
• Morning for fresh start feel
• Test what reaches inactive subscribers

Frequency Optimization

How often to send matters as much as when.

Finding the Right Frequency

Too Few Emails:

• Subscribers forget you
• Miss revenue opportunities
• Lose mind share

Too Many Emails:

• List fatigue
• Higher unsubscribes
• Lower engagement per email
• Spam complaints

Frequency Benchmarks

By Industry (typical ranges):

• E-commerce: 2-5 emails per week
• B2B: 1-2 emails per week
• Media/Publishing: Daily to weekly
• SaaS: 1-4 emails per month
• Non-profit: 1-2 emails per month

Frequency Testing

How to Test:

1. Segment list into frequency groups
2. Send different amounts to each
3. Measure engagement and revenue
4. Find optimal balance

Metrics to Watch:

• Open rate per email
• Total opens per subscriber
• Unsubscribe rate
• Revenue per subscriber

Preference Centers

Let Subscribers Choose:

• Frequency options (daily, weekly, monthly)
• Content type preferences
• Communication channels
• Pause options

Benefits:

• Reduces unsubscribes
• Improves engagement
• Shows respect for preferences

Time Zone Considerations

Reaching global audiences at the right time.

Time Zone Strategies

Option 1: Send in Recipient's Time Zone

Send at 10 AM local time for each recipient.

Pros:

• Optimal timing for everyone
• Highest engagement potential
• Professional appearance

Cons:

• More complex to implement
• Requires accurate time zone data
• Some ESPs don't support well

Option 2: Segment by Region

Create segments by geographic region, send separately.

Pros:

• Simpler than individual time zones
• Good balance of optimization and simplicity
• Works with any ESP

Cons:

• Still requires multiple sends
• Some recipients get less optimal times

Option 3: Single Send Time

Pick one time and send to everyone.

Pros:

• Simplest to manage
• Works for small, concentrated lists
• Quick to execute

Cons:

• Poor timing for some recipients
• Disadvantages certain regions
• Lower overall engagement

Collecting Time Zone Data

Methods:

• Ask at signup
• Infer from IP address
• Derive from phone number
• Use location data from activity

Important: If you don't have time zone data, you can't optimize for it.

Testing Your Send Times

Finding what works for YOUR audience.

A/B Testing Send Times

Basic Approach:

1. Split list randomly
2. Send same email at different times
3. Compare results
4. Apply learnings

What to Test:

• Same day, different times
• Same time, different days
• Morning vs. afternoon vs. evening

Time Testing Best Practices

Test One Variable: Only change the send time, not the content.

Sufficient Sample Size: Need enough recipients for statistically significant results.

Multiple Tests: One test isn't definitive. Confirm with multiple experiments.

Consider Seasonality: Results may vary by season, holidays, events.

Send Time Optimization Tools

AI-Powered Solutions: Many ESPs offer machine learning-based send time optimization.

How They Work:

• Analyze individual subscriber behavior
• Predict optimal time for each person
• Send automatically at predicted best time

Considerations:

• Requires historical engagement data
• Works better with larger lists
• Not always more effective than well-tested manual times

Advanced Timing Strategies

Going beyond basic optimization.

Predictive Send Time

Individual Optimization: Predict the best send time for each subscriber based on their behavior.

Data Used:

• Historical open times
• Click times
• Website activity patterns
• Purchase timing

Implementation:

• Some ESPs offer built-in
• Can build custom models
• Requires sufficient data per subscriber

Event-Based Timing

Triggered by Behavior: Send based on actions, not clock time.

Examples:

• Website visit → Email within 1 hour
• Cart abandonment → Email at 1, 24, 48 hours
• Content download → Follow-up next day
• Purchase → Review request 7 days later

Benefits:

• Always relevant timing
• Based on recipient readiness
• Higher engagement

Sequential Timing

Coordinated Sequences: Plan timing across multiple emails.

Example Campaign:

• Day 0: Announcement
• Day 2: Benefits detail
• Day 4: Social proof
• Day 6: Urgency/deadline

Considerations:

• Consistent timing builds expectation
• Varying times can increase visibility
• Match urgency to timeline

Real-Time Optimization

Live Adjustments: Monitor campaign performance and adjust mid-send.

How It Works:

1. Send to small initial segment
2. Measure early results
3. Adjust timing for remaining recipients
4. Optimize in real-time

Requirements:

• Fast analytics
• Flexible sending infrastructure
• Large enough list to segment

Timing and Deliverability

How timing affects whether emails arrive.

Server Load Considerations

ISP Processing:

• Major ISPs may throttle high-volume sends
• Spreading sends can improve delivery
• Early morning may see less competition

Practical Impact: For large lists, consider spreading sends over hours rather than all at once.

Engagement Signals

Timing Affects Engagement:

• Higher engagement = Better sender reputation
• Better reputation = Better deliverability
• Optimal timing creates virtuous cycle

The Connection: Poor timing → Low engagement → Reputation damage → Deliverability problems

Learn more about protecting your sender reputation in our email deliverability guide.

Send Spacing

Between Campaigns:

• Don't send multiple campaigns same day
• Space promotional emails appropriately
• Balance automated and broadcast sends

Within Campaigns:

• Large lists: Spread over time
• International: Stagger by time zone
• Urgent: Send as quickly as delivery allows

Common Timing Mistakes

Avoid these pitfalls.

Mistake 1: Blindly Following Benchmarks

Problem: Using industry benchmarks without testing your audience. Fix: Use benchmarks as starting points, then test.

Mistake 2: Ignoring Time Zones

Problem: Sending at 10 AM your time to global audience. Fix: Segment by region or use send-time optimization.

Mistake 3: Over-Sending

Problem: Too many emails causing fatigue. Fix: Test frequency, offer preferences, monitor unsubscribes.

Mistake 4: Inconsistent Timing

Problem: Random send times confuse subscribers. Fix: Establish predictable patterns (unless testing).

Mistake 5: Not Testing

Problem: Never testing to find optimal times. Fix: Regular A/B testing of send times.

Mistake 6: One-Size-Fits-All

Problem: Same timing for all email types. Fix: Match timing to email purpose and audience.

Building Your Timing Strategy

A framework for optimization.

Step 1: Know Your Audience

Gather Data:

• Where are they located?
• When do they typically engage?
• What are their work/life patterns?
• Device usage patterns?

Step 2: Start with Benchmarks

Initial Approach:

• Use industry benchmarks as starting point
• Consider your email type
• Account for audience characteristics

Step 3: Test Systematically

Testing Plan:

• Test day of week (same time, different days)
• Test time of day (same day, different times)
• Test frequency
• Document all results

Step 4: Implement Findings

Apply Learnings:

• Update default send times
• Segment where needed
• Set up automation timing
• Configure time zone handling

Step 5: Continue Optimizing

Ongoing Improvement:

• Regular testing cadence
• Monitor for changes
• Adapt to audience evolution
• Try new approaches

Timing Checklist

Before Sending

• [ ] Considered recipient time zones
• [ ] Chosen optimal day based on email type
• [ ] Selected tested/benchmark time
• [ ] Checked recent send history (not over-sending)
• [ ] Reviewed automation timing

Testing Plan

• [ ] Testing calendar established
• [ ] Variables isolated properly
• [ ] Sample sizes sufficient
• [ ] Results being documented
• [ ] Learnings being applied

Optimization

• [ ] Time zone data collected
• [ ] Segments by region created (if needed)
• [ ] Frequency tested
• [ ] Preference center offered
• [ ] Send time optimization tools evaluated

Data Quality and Timing

Invalid emails affect your timing optimization.

The Data Quality Connection

Invalid Emails Skew Timing Analysis:

• Bounces count as non-opens
• Distorts engagement patterns
• Makes timing tests unreliable

Clean Data Enables:

• Accurate engagement analysis
• Reliable timing tests
• True optimization

Before Timing Optimization

Verify Your List: Ensure you're optimizing timing for valid, deliverable addresses using email verification and email list cleaning.

Why It Matters: If 10% of your list is invalid, your timing analysis is based on flawed data. Maintain email list hygiene for accurate optimization.

Conclusion

Email timing is both science and art. The science gives us benchmarks and testing frameworks. The art is understanding your unique audience and continuously optimizing.

Key timing principles:

1. Benchmarks are starting points: Test to find your optimal times
2. Know your audience: Different audiences have different patterns
3. Test systematically: One variable at a time, document results
4. Consider time zones: Respect your recipients' local time
5. Balance frequency: Find the sweet spot between too few and too many

Perfect timing means nothing if emails don't reach the inbox. Invalid addresses hurt deliverability and distort your timing data.

Ready to ensure your carefully timed emails reach valid subscribers? Start with BillionVerify to verify your list and maximize the impact of your timing optimization.