Warm-Up Period

What is a Warm-Up Period?

A warm-up period is the gradual process of building trust and reputation for a new email domain or inbox with internet service providers (ISPs) and email providers like Gmail and Outlook.

During warm-up, you progressively increase your email sending volume over 2-6 weeks, starting with just a few emails per day and slowly building up to your target volume. This signals to email providers that you're a legitimate sender with consistent, engaged recipients.

Why Warm-Up Matters in 2024

Email deliverability has become more stringent:

• Gmail and Outlook use AI-powered spam filters that flag new domains sending high volumes
• Sudden sending patterns trigger spam filters automatically
• Without proper warm-up, 50-80% of cold emails may never reach the inbox

How to Warm Up Effectively

Progressive Sending Schedule

Week 1: Foundation

• Day 1-3: 2-5 emails daily
• Day 4-7: 5-10 emails daily
• Focus: Get real replies, not just sends

• Day 8-14: 10-20 emails daily
• Maintain 25-40% response rate on warmup emails
• Start mixing in real prospect outreach

• Day 15-21: 20-40 emails daily
• Day 22-30: 40-50+ emails daily
• 1:1 ratio of warmup to campaign emails

Technical Best Practices

During Warm-Up:

• Disable open tracking and link tracking initially
• Use secondary domains, not your primary domain
• Send to engaged contacts who will reply
• Vary sending times naturally
• Keep conversations going (multiple back-and-forth emails)

• Sending bulk emails immediately
• Buying email lists
• Ignoring bounce rates
• Using identical templates
• Overnight volume spikes

Signs Your Warm-Up Is Working

Positive Indicators:

• Emails landing in Primary folder, not Spam
• Open rates above 50%
• Reply rates above 20%
• Consistent inbox placement across providers

• Emails going to Spam folder
• High bounce rates (>5%)
• Sudden drops in open rates
• Spam complaints

Tools and Automation

Manual Warm-Up:

• Personal email conversations
• Networking outreach
• Existing customer communications

• Smart warm-up tools with peer-to-peer networks
• Auto-reply simulation
• Inbox placement monitoring
• Reputation tracking dashboards

Key Takeaways

• Warm-up period is 14-30 days of gradually increasing email volume
• 21-day warm-up shows 30% higher open rates vs 14-day
• Start with 2-5 emails/day, build to 40-50/day
• Focus on real conversations and replies
• Use secondary domains for cold outreach
• Monitor inbox placement, not just delivery
• Proper warm-up prevents long-term deliverability issues