What are IP address pools?

IP pools are groups of dedicated IP addresses that are used to manage the sending reputation of your individual mail streams.

Why use IP pools?

The main purpose of IP pools is to protect your sending reputation for your most important email. Most important email, however, means different things to different users, so let’s go through a couple use cases for IP pools. 

Marketing & Transactional

Transactional email provides important, often high-priority information, giving it a high engagement and deliverability rate. Marketing email, on the other hand, is more likely to be sent to spam filters, since it can be seen as unwanted by users and Internet Service Providers.

When marketing and transactional email are sent over the same IP, it can bring down the overall sending reputation, sending more of the transactional email to the spam folder. 

To solve this, some users separate their marketing and transactional mail streams to go through different IP pools. This helps maintain the high inbox placement of your transactional email while you work on improving the deliverability rate of your marketing email.

Note: For those using Twilio SendGrid, we recommend creating a subuser to separate your marketing and transactional email rather than IP pools. Creating a subuser not only keeps your separate sending organized, it also makes it easier to maintain suppression groups and view aggregate stats for the individual mail streams.

Recipient Engagement

Another use case for IP pools is to segment different levels of subscriber engagement. Users can set up high, medium, and low IP pools. High represents the good or highly engaged recipients, while a low pool features subscribers with much lower engagement rates. 

Subscribers are added to a pool based on various email metrics, such as open rate, spam complaint rates, unsubscribe rates, and bounce rates. 

By separating the IP pools by engagement, you ensure that the sending reputation and delivery rate for the most engaged recipients is the strongest. You can then work to improve your deliverability rate for the other IP pools without having to worry about it affecting your VIP subscribers.

Interested in learning how to boost your deliverability rate? Download Twilio SendGrid’s Email Deliverability Guide

Do I need to create IP pools?

Find out with this quick questionnaire. Ask yourself:

    1. Do you have multiple dedicated IP addresses?
    2. Are you sending more than 25,000 messages daily?
    3. Do you send multiple types of email (e.g. marketing email and transactional email)?

If you answered yes to those questions, then it would probably be helpful to group your IPs into IP pools to better manage your sending reputation. 

If you answered no to most of these questions, then you’re not quite ready to configure IP pools. In fact, too many IPs can look suspicious to mailbox providers. If you’re sending too small of an amount of email across numerous IPs, you can look like a spammer trying to disguise your sending by thinly spreading your reputation across a wide range. This is a sure-fire way of hurting your sending reputation.

For more information on IPs and how many you should use for your email program, read our article, IP Allocation: How Many IPs Do I Need?

Curious how IP pools work at Twilio SendGrid?

Great! Check out our docs page to see how you can manage IP pools through Twilio SendGrid. For additional assistance, partner with our experts to help you warm up your IPs, improve your sending reputation, and increase your deliverability rate. 



Julie Griffin
Julie is the content marketing associate at SendGrid, helping to write and edit the blog, as well as enhance SendGrid’s SEO efforts. When she isn’t at the office, you’ll find her buzzing around Denver’s coffee shops, breweries, and yoga studios.