Domain Warmup: How It Works (Fixed-Stage Model)

This guide explains how the platform's domain warmup works using a fixed-stage model — helping you build sender reputation and improve email deliverability safely.

Domain warmup is the process of gradually increasing your daily email volume to build a trusted sender reputation with inbox providers like Gmail, Outlook, and Yahoo.

Without proper warmup, new domains are more likely to:

• Be flagged as spam
• Experience high bounce or complaint rates
• Face email delivery blocks or delays

The platform automates this process to help you build trust and maximize email deliverability.

This system uses a fixed-stage, gradual warmup model, which means:

• Each stage has a predefined daily sending limit.
• Progression only occurs when the full daily limit for the current stage is reached.
• If the daily limit is not met, the domain remains in the same stage.
• There are no hourly sending limits.
• You must send emails through the warming domain for progress to be tracked.

• For newly created domains: Warmup is automatically enabled when the domain is created and verified. No manual action is needed.
• For existing domains: Warmup must be enabled manually. When you enable warmup on an existing domain, the system automatically analyzes past email activity and Google Postmaster reputation data (if integrated).

Based on this analysis, it recommends the most suitable starting stage to ensure smooth warmup progression.

Email warmup is available for both agencies and sub-accounts using dedicated domains.

Integrating your domain with Google Postmaster Tools gives you access to key deliverability data, including:

• Domain reputation (High, Medium, Low, Bad)
• Spam complaint rates
• Authentication status
• Delivery and error metrics

If Google Postmaster is not yet connected or no data is available, the domain dashboard will notify you and guide you through setup.

• Send emails consistently every day.
• Use verified, opt-in contact lists.
• Avoid sudden spikes in volume.
• Avoid switching sender domains mid-campaign.
• Respect daily warmup limits to avoid future enforcement blocks.

Your domain completes warmup when it reaches Stage 15 (250,000 emails/day). At that point, you'll see a "Warmup Complete" label in the domain dashboard, and full-scale sending will be supported.