What is IP warming?
A good analogy for IP warming is how you warm up to someone that you have just met. When you meet someone for the first time, you would not be very chatty with said person as you don’t really know that person. You might start off with a simple “Hello” and introduce yourself. The longer you know the person and the more you interact with that person, you may reach a level of familiarity where you can talk about anything for any length of time.
Why do you need to perform IP warming?
The basic idea behind IP warming is for your mail server to be a familiar sender to your recipients’ ISPs. This means you start off with sending a small number of emails to a particular email domain. After you have sent a small number of emails for a while, you can ramp it up slowly until you are able to send large quantities of emails to that domain.
If you attempt to send out large amounts of emails without first performing IP warming then you’ll find ISPs branding you as a possible spammer since they have no idea who you are in terms of your sending reputation.
How to perform IP warming?
Generally speaking, if you send less than 50,000 emails per month, you won’t need to perform IP warming as you will not have triggered any email reputation filters on the ISPs.
On the other hand, if you plan to send out large (> 50,000) amounts of emails per month, you will need to take note of the following steps to warm up your IP.
- Determine a sending schedule for the warming up process.
- Select a subset of your mailing list like users who have signed up for a trial of your product/service.
- Send them an email asking them about their experience using the trial and let them know if they require any assistance, they just need to reply to the email that they had just received. (follow the schedule that you have determined in Step 1)
- Their replies to your email will help to cement your reputation as a responsible mailer with the ISPs.
Example email sending schedule for warming up IP
Split your monthly total emails evenly into 30 daily batches. So, if you are sending 60,000 emails per month, you should send 2,000 emails per day during the warm up period (estimate 1 to 2 months).
Take note that you need to warm up all ISPs daily so be sure to split your emails between all the ISPs so that each ISP will receive a substantial amount of emails. If you don’t make sure that each ISP receive a substantial amount of emails daily during the warm up period, your sending reputation may not get the boost that you desire.
Adjust the amount of emails sent if deliverability rate is not good
The above is just a simple example of how to determine a warm up schedule. Your needs may not be similar to what is described here. Keep track of your deliverability rate during your warming up period. If you are getting good deliverability rate, then keep up your schedule. On the other hand, if you see a slump in your deliverability, you should lower the number of emails that you are sending.