Warm-up best practices
What is email warm-up?
Email warm-up is a process that builds trust for a new or inactive email address.
When warm-up is enabled, we gradually start sending emails to it from a trusted network of inboxes. These emails are opened, replied to, and interacted with, creating positive engagement signals.
These positive signals show email providers (i.e. Gmail, Outlook, Yahoo, and others) that you’re a legitimate sender. Over time, this helps more of your emails land in inboxes instead of spam.
Can I still use my inbox during warm-up?
Yes! Email warm-up does not block or limit your inbox. You can continue sending and receiving emails as usual while warm-up is running.
Warm-up operates in the background and is designed to complement your normal email activity, not replace it.
When will I see the benefits of warm-up?
Warm-up works gradually. You can send outreach emails immediately after starting the warm-up process, but the strongest deliverability benefits appear after a few weeks of consistent activity, once inbox providers have accumulated enough positive engagement signals.
This is normal and expected. Sender reputation is built over time, not overnight.
Why and when should you use it?
You should use warm-up when:
- You’re sending from a new domain or email address.
- Your address hasn’t been used in a while.
- You’re planning to send emails at higher volumes than before.
- You’ve had deliverability issues in the past (e.g. landing in spam).
If you’re unsure whether you need to warm up, you can check your sender health using our free Email Reputation tool. It runs a quick analysis of your DNS records, blacklist status, and spam signals. If your score is below 50, we strongly recommend starting warm-up before launching any real campaigns.
How long should I keep warm-up enabled?
We recommend keeping warm-up active for at least 30 days. This period allows your sending volume to increase gradually and helps email providers build trust with your address.
Here’s what that typically looks like:
- Days 1–3: just a few emails per day
- Days 4–10: volume starts to increase
- Days 11–30: stable daily activity (~40–50 emails/day)
You can begin sending real emails such as cold outreach or newsletters after the first 10–14 days, once your warm-up volume has started to climb. But it’s important to go slowly: send to a small, high-quality segment of your list first, and gradually scale from there. Avoid sending high volumes too early, as that can damage your reputation before it’s fully established.
For best results, we recommend keeping warm-up active for 60 to 90 days. This helps reinforce your reputation even while you begin real outreach. Think of it as running in the background. Mailmeteor continues to generate activity that boosts trust while you scale up safely.
If you stop sending for a while (e.g. after a pause in outreach), consider restarting warm-up for a week or two to refresh your reputation before sending again.
Key takeaways
To get the most out of email warm-up:
- Keep sending patterns consistent
- Avoid sudden spikes in email volume
- Send emails to people who are likely to read and reply to
- Avoid spam-like content or purchased lists
If you’re patient and consistent, warm-up sets you up for better inbox placement long-term.
Next steps
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