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How to Build Trust Before You Send

Before you send your first cold email, there's one critical step: warm up your domain. Without it, your emails are likely to go straight to spam.

This guide gives you a complete 30-day warm-up plan and explains how to automate the process.


Why You Need to Warm Up Your Domain

Cold outreach from a new domain looks suspicious to inbox providers. Warming up builds trust and reputation gradually.

Skipping this step leads to:

  • Low open rates
  • High bounce risk
  • Spam folder placement

The 30-Day Warm-Up Plan

Week 1: Start Slow (5–10 emails/day)

  • Send emails manually to trusted contacts
  • Focus on real conversations
  • Respond promptly to replies

Week 2: Scale to 15–25 emails/day

  • Gradually include cold email templates
  • Ask recipients to reply and mark as important

Week 3: Use a Warm-Up Tool

Automate engagement with platforms like:

  • Mailwarm
  • Lemwarm
  • Instantly

These tools:

  • Exchange emails in a network
  • Simulate real replies, opens, and stars

Week 4: Hit 30–50 emails/day

  • Keep an eye on domain reputation
  • Mix manual and automated warm-ups

Tools We Recommend

  • Instawarm: Great for new domains
  • Mailreach: Clean reporting dashboard
  • Instantly Warmup: Built into cold outreach tool

Tips:

  • Don’t start your campaign until warm-up is complete
  • Set up SPF, DKIM, and DMARC before sending
  • Use different inboxes and rotate senders

Need help with authentication? Check our SPF, DKIM, DMARC Explained guide

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