How Sending Windows Affect Your Deliverability

Most people think deliverability is only about how many emails you send. But Gmail, Outlook, and other ESPs also watch when you send.

If your domain blasts emails at 3 AM or sends 200 in the exact same minute, that looks suspicious. Deliverability isn’t just volume — it’s timing.

🕒 Why Sending Windows Matter

• Natural behavior: Real humans don’t send 50 emails at the exact same second.
• ESP detection: Gmail/Outlook algorithms flag unnatural bursts.
• Trust factor: Consistent, human-like timing builds credibility.

👉 Related reading: Scaling Outreach Safely: How Many Emails Per Day is Too Many?

⚠️ Mistakes Teams Make With Sending Times

1. Blasting campaigns at once → Creates spikes, kills trust.
2. Ignoring time zones → Sending at 2 AM in the recipient’s inbox looks off.
3. Too predictable patterns → “Every email at exactly 9:01 AM” feels automated.

✅ Best Practices for Sending Windows

• Distribute sends gradually over hours, not minutes.
• Align with working hours in your target market’s time zone.
• Randomize slightly to mimic natural human sending.
• Use warm-up tools that spread sends automatically.

👉 Related reading: Warm-Up Mistakes to Avoid: What Hurts Your Deliverability

🚀 AutoWarm’s Advantage

AutoWarm includes configurable sending windows:

• Spread warm-up emails naturally across your chosen time window.
• Randomized send intervals to mimic real inbox behavior.
• Perfect for multi-time zone outreach campaigns.

This ensures your domain warms up like a human — not a bot.

✅ Final Takeaway

Deliverability isn’t only about how many emails you send, but when. With smart sending windows, you avoid spikes, mimic real behavior, and build long-term trust with ESPs.

AutoWarm automates this, making sure your warm-up (and outreach) looks natural every single day.