ip warm ups

How many unique message streams do I have?

Separating message streams on separate IP's is a best practice and ensures that the sending activity from your Marketing emails doesn't impact your ability to get your Transactional emails delivered to the inbox for example.

Different message stream examples are: transactional, marketing, individual brands, regions, etc.

Keep in mind senders with volume less than 500k messages per month or with inconsistent volume from week to week may not have enough volume to build and maintain a positive sending reputation with mailbox providers. In this case, a shared IP pool may result in better delivery and deliverability.

For the warm up plan:

During weeks 1-2 send to your most active subscribers - those who have opened/clicked in the past 30 days

During weeks 3-4 you can expand to subscribers who have opened/clicked in the past 60 days

During the first 6 weeks do NOT send to subscribers who have not opened or clicked in the past 90 days

What is the breakdown of domains in your 25K list?

Assuming it is mixed between the big 4 domains and some of the bigger cable providers, here is my suggestion.

For each SMTP you setup and build, assuming you do it using 1 IP | 1 Domain Name, the following schedule will work.

Week 1
5 Emails per hour, per ip

Double it up every week

Do this continuously for the next 12 weeks and you should be in good shape.

Also, I would not send this 24 hours a day, try to limit it to 12-18 hours per day max.

Hope this helps.

IP warmup is gradually increasing the volume of emails you send over time.

When you setup a fresh email server, your IP doesn't have any reputation. You get flagged as spam when you attempt to deliver large quantity of emails with this IP.

We do a IP warmup to avoid this from happening. You start sending slowly. I always start with 20 emails per hour during the first day. And then increase this to 35 emails per hour during the next day.

This gives the opportunity for ISPs to build a reputation score for your IP. Reputation is calculated based on the content you send and user interaction to your emails and many other factors.

Important thing to understand is that warming up your IPs will not give you an inbox guarantee. It all comes down to the content you send and how targeted your list is.