Unlimited email sending volume for your success

Bulk Mail Server®

You might run across the idea of warming up an IP address to improve your sending delivery performance. Warming up your IP allows you to gradually establish a good mass email sender reputation.

IP addresses start out “COLD” meaning they haven't been used to send email. It’s best to start small and gradually send to larger volumes of prospects.

IP warming is a gradual process that helps you establish a reputation as a legitimate email sender. When a receiving server notices email coming from a formerly dormant IP address, they will scrutinize the traffic coming from that IP address.

Send first email to your personal email address at yahoo, gmail and hotmail, it is expected to be received to SPAM folder, now try to mark it as safe like the screenshots show.

Mark as safe or not junk to enhance smtp server reputation

Mark as safe or not junk to enhance smtp server reputation


Mark as safe or not junk to enhance smtp server reputation

It’s best to start small and gradually send to larger volumes of prospects. This give receiving servers time to observe your sending patterns and behavior and allows you build a solid sending reputation.

If a previously unused IP starts sending 100.000 emails / day without any warming, recipient email servers must assume the worst that you are a spammer, and this will negatively affects your bulk email server sending reputation.

Get ready to warm up your mass email server IP address:

  • Don’t start your IP warming with old lists! Having high delivery rates with your initial campaigns will help build your IP’s reputation
  • Send newsletters content that your audience want.
  • Remove unengaged emails.
  • Send email messages at an appropriate frequency.


- It is much easier to establish a positive reputation as a new sender, than it is to repair an existing reputation.

- If your mailing patterns are infrequent -- for example, only one mail campaign per month -- avoid sending more than 5,000 - 10,000 messages per day.


Warming up IP Address

The key to warming your IP address is to spread out your initial sends over multiple days. For example, If you plan on sending 50,000 emails a week, it is recommended that you split your lists into at least four groups with limit of no more than 10,000 recipients in each list.

Email only one groups a day over the first few days. A good rule of thumb for larger ramp-ups is to start your sending at 10,000 prospects per day. Assuming your bounce rate stays below 10% and your spam complaint rate stays below 0.1% on those sends, you can safely double your sending per day over the next few weeks until your intended sending volume is reached. For example, if you want to send 100k emails a week, you should ramp up like this:

Week Emails per day Total per week
Week 1 2,800 a day for first 7 days 20,000
Week 2 4,300 a day for 7 days 30,000
Week 3 5,700 a day for 7 days 40,000
Week 4 7,000 a day for 7 days 50,000
Then add about 3 - 5000 a day for each week.

It is recommended to keep a consistent mail volume from one business day to another which is better than having a large volume spike on one day of the week and no email sent on remaining days of the week.

Expected bounce rates

Monitor the bounce rates of your lists and stop mailing if the bounce rate of your first one or two groups exceeds 10%. This is a sure sign that your list needs maintenance! Clean up your list, and then resume sending to the remainder of the groups.