Here is a comparison of Cold and warm sender domains

Before warming up

If you think your domain needs a warmup, follow these best practices for better impact in your warmup process.

• Authenticate your sender domain with Zoho Marketing Automation. To learn how to set up SPF and DKIM text records, click here.
  
• Maintain proper 'whois' information for your domain.
  
• Make sure you have a business domain and not a public sender domain.
  
• Make sure your mailing list has only permission based leads.
  
• Remove email addresses with typos, expired addresses, and role/group addresses from your mailing list.
  
• Set up tools to check your spam complaints, delivery errors, etc. For example, if your lead base has significant Gmail users, you can use Gmail's Postmaster Tool.
  

How to warm up your cold domain

Warming up a sender domain means regularly sending limited emails for several days, until your email delivery is ensured and the domain reputation is built.

• Start with leads who have recently engaged, and those who are more likely to open your emails. This will result in more open rates, and will create a good rapport with the recipient systems. Later, you can gradually add the leads who are less likely to give a positive response to your emails. For example, leads who signed up recently are more likely to give positive responses.
  
• You can segment your mailing list and target leads who are more interested in your emails.
  
• Zoho Marketing Automation recommends you to start with an average count of 5 - 10% of recipients per day from a sender domain and avoid sending hundreds of emails in the beginning. Once you're sure that your emails are getting good responses from the recipients and has a good delivery rate, gradually increase your email count by 5% of leads per day. If you have a high lead volume, you can start sending emails with 50 - 100 leads and increase by 50 leads per day.
  
  If your email gets undelivered or has unsubscribes and spam complaints, you can slow down and reduce your emails-per-day to the count in the beginning of warm up again. Follow a similar pattern by observing your lead response and email delivery, and then increase your email count by five emails per day. This will help your domain warm up.
  

If you have a high volume of leads in a single recipient domain, you can:

1. First, send test emails and check delivery rate.
   
2. Split and add them to various lists having other recipient domains as well. Distribute the concentrated crowd.
   
3. For example, if you have more Gmail leads, then distribute them into various lists. You can send them marketing emails with a gap of a few days for every list. By doing this, you can avoid email delays and throttles.
   

1. While you warm up your domain, pay close attention to your open-click rates, spam complaints, bounces, unsubscribes, low domain reputation, and spam traps.
   
2. For leads with a communication gap of more than one year, avoid sending marketing emails. Know their interest through a winback campaign (re-engagement email).
   
3. Recommend that your recipients add your email address to their leads or safe senders' list. This ensures better inbox placement rate. To learn how to whitelist a sender domain, click here.
   

After warm up

Domain warm-up is not a single day workout but a regular practice with which you can ensure good email delivery. It may seem quite complex in the beginning, but once you've started warming up a domain, you'll easily learn how to improve your open-click rates and how to avoid email delivery issues. This understanding of the email deliverability basics will help you build your email marketing stronger.