Deliverability & Authentication

How to Warm Up a New Domain

A new domain has no sending reputation. Warming up means gradually increasing email volume to build trust with ISPs like Gmail, Outlook, and Yahoo. OutSends automates this process.

Time: 20 min
Level: Advanced
domain warm-up deliverability sender reputation dkim

What you'll need

Before you start, make sure you have the following ready.

  • A new domain configured with DKIM, SPF, and DMARC
  • An OutSends account
  • A small list of engaged contacts (50-100)

Step-by-step guide

Follow these steps to complete the setup.

Authenticate your domain

Configure SPF, DKIM, and DMARC DNS records. OutSends provides the exact values for each record type.

Start with 10-20 emails/day

Send only to your most engaged contacts who are likely to open and reply. Avoid spam traps.

Increase volume gradually

Add 20-30% more emails every 2-3 days over a 4-week period. OutSends smart-warming handles this automatically.

Monitor deliverability metrics

Watch bounce rates, open rates, and spam complaints. If bounce rate exceeds 3%, pause and investigate.

Maintain consistent sending

Once warmed up, send regularly. Long pauses can degrade reputation and require re-warming.

Tips for best results

Pro tips to get the most out of this setup.

  • Never warm up on rented or purchased lists — only engaged contacts
  • Respond to replies within 24 hours to show positive engagement signals
  • Use a dedicated subdomain (mail.yourdomain.com) to protect your main domain

Frequently asked questions

How long does domain warm-up take?

Typically 2-4 weeks depending on your target volume.

Can I send normally during warm-up?

No. Stick to the warm-up schedule strictly. Exceeding volume too early can damage reputation permanently.

What happens if I stop sending after warming up?

Reputation decays after 2-3 weeks of inactivity. Resume with reduced volume (50% of max) and rebuild.

Related guides

Explore more how-to guides for OutSends.

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