Email Whitelist: What Is It Good For and Why Do You Need It

What Are the Email Whitelist?
Denys Romanov Denys Romanov 07 february 2023, 10:05 373
For beginners

Whitelists are one of the essential things to know about if you engage with customers via email. They are a list of IP addresses or domains, created by internet service providers (ISPs), that are allowed to send emails to a specific mail server. It would be beneficial to have your IP address added to whitelists because it increases the chances of your messages getting to the intended recipients. It also improves your sender reputation, a critical factor for your brand. 

However, whitelists aren’t a magic bullet that guarantees 100% deliverability. Any company may set up their mail server to use its preferred whitelists or ignore them altogether. In general, blacklists are considered more important for successful email delivery than whitelists. But even so, whitelisting has a major influence on your delivery rate.

Examples of Whitelists

There are many whitelists you can add your IP address to. Some are free while others require payment. Overall, they improve your sender reputation and deliverability rate. 

Keeping track of your whitelisting does not require much effort, so be sure to add to as many as possible. Then keep your rates high and follow the recommended industry practices to ensure you are not delisted.

1. Everest Sender Certification


Everest is a well-known email deliverability platform used by over 10,000 businesses worldwide. One of its features is Sender Certification, which adds the IP address from which you send messages to a whitelist. Many email providers use this whitelist, so having your IP address on it means that your message will be more likely to get to the intended inboxes instead of being marked as spam.

This program also lets you monitor critical metrics concerning your email deliverability. For example, you can see how many times an email recipient reported your message as spam or how many of your emails got into spam traps. You also get access to an on-call security and compliance team, but this service doesn't come cheap.

2. Certified Senders Alliance (CSA)


The Certified Senders Alliance (CSA) is a project created by the Association of the Internet Industry and the German Direct Marketing Association. It's a central email whitelist for bulk senders. Many ISPs and email providers participate in this whitelist, so having your IP address on it increases the chances of your emails getting to the intended recipients.

You can apply to get your IP address added to the CSA whitelist, and you must meet certain criteria to be considered. For one, you must have a clear brand identity and full control of the servers from which you send your messages. You must also include revocation and unsubscribe functions in your emails. Likewise, you must implement closed-loop authentication for them. 

If you meet the criteria, you can submit samples of your emails to CSA during your application. If approved, you'll pay a fee and get your IP address added to the CSA whitelist.

Why Do You Need to Be on a Whitelist?

1. To Improve Your Deliverability Rate

Deliverability rate refers to the percentage of your messages that arrive in the recipient's inboxes. Many factors influence it, but one of the notable options to be on the safe side is to add your IP address to a whitelist. Being on a whitelist means lower chances of email providers blocking your emails from getting to their users. 

Mailbox providers put a lot of effort into making sure that their users are protected from spam. One of the things they do is participate in whitelists to know which IP addresses are legit or not. Having your IP address on a whitelist means that mailbox providers will likely see your messages as legit and not mark you for spam.

2. To Increase Your Sender Reputation

Sender reputation is a score that an internet service provider (ISP) assigns to your brand. The better your score is, the higher the chances of the ISP delivering your emails to recipients on their network. Several factors affect this score, such as the number of complaints to the ISP about your messages, the number of emails you send, or whether they fall into the ISP's spam traps. But, by default, ISPs assign higher scores to brands that are included in whitelists than those that aren’t. 

Having a high sender reputation goes a long way in validating your brand and being in a whitelist is a proven way to get a higher score.

Things to Note

Email marketing has a lot of tenets. It’s not nearly enough to know how to create effective marketing campaigns. You must also work to ensure that your emails get to the intended recipients. The primary thing to consider is to choose a reputable email service provider (ESP), e.g., UniOne, that you will use to send them. Many ESPs, including UniOne, allow you to get a dedicated IP address, which reduces the chances of your brand being implicated due to the nefarious activities of other users. You can then include this IP address on a whitelist to enhance your email deliverability.

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