TABLE OF CONTENTS

What is Domain Warmup?

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

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

What Warmup Model Is Used?

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
Important: Sending beyond the daily limit is allowed and emails will not be blocked.

Warmup Stage Breakdown

Stage
Daily Limit
1
1,000
2
2,500
3
5,000
4
6,500
5
8,000
6
10,000
7
14,000
8
20,000
9
25,000
10
35,000
11
50,000
12
80,000
13
125,000
14
175,000
15
250,000


Once the daily limit is reached, the system pauses additional sending from that domain until 12:00 AM UTC the next day. The next stage will automatically begin if the full daily limit was reached.

When Does Warmup Start?

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 will automatically analyze:

  • Past email activity
  • Google Postmaster reputation data (if integrated)

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

How to Start Warmup for an Existing Domain:

  1. Navigate to the domain in your Email Setup screen
  2. Click Start Warmup
  3. Begin sending emails using that domain

Sending activity is required for the system to track warmup progress.

Who Can Use Email Warmup and How to Enable It

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


To enable warmup for an agency domain:

  1. Go to Agency Settings
  2. Click Email Services
  3. Select SMTP Service
  4. Go to the Dedicated Domain and IP tab
  5. Choose your domain and click Start Warmup


To enable warmup for a sub-account domain:

  1. Go to the Sub-Account Settings
  2. Click Email Services
  3. Select SMTP Service
  4. Go to the Dedicated Domain and IP tab
  5. Choose your domain and click Start Warmup

Google Postmaster Integration (Recommended)

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.

Best Practices for a Successful Warmup

  • 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

When Is Warmup Complete?

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