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The dirty truth about email lists and how to scrub them with email list cleaning

 A clean email list is the ultimate email performance enhancer, if you manage it correctly. When these lists get dirty, your sender reputation suffers, and that hurts your deliverability big time. Here’s how to prevent loss and get the most out of your list management.



Pardon our French, but nothing delivers a bigger sucker punch to your deliverability than a dirty email list.

Email lists aren’t just for organizing and storing contacts, they are the communications database you use to segment your campaigns, target your messaging, and build your engagement. If your lists is filled with invalid addresses, or unengaged users, your sender reputation, and therefore your deliverability, can plummet. Fast.

Building and maintaining a healthy email list is a process that can be managed with some simple practices and tools. Read on to learn more about the importance of email list cleaning and how to do it.

What is email list cleaning?

The goal of email list cleaning is to remove invalid and unresponsive email addresses from your contacts on a regular basis. The email list cleaning process involves verifying email addresses with a variety of tools including email address verification, data validation, and hygiene best practices based on recipient engagement.

Why do you need to clean your email lists?

Great question. 

Regular list maintenance leads to lower bounce rates, increased engagement, and improved deliverability by ensuring your messages are sent to people who are interested in your content and services. ISPs use actions like open and click-through rates to determine inbox placement, but your engagement metrics heavily influence your deliverability success as a whole.

ESPs charge based on the number of emails sent. Sending with a clean email list supports your ROI by ensuring messages are sent to legitimate recipients.

4 tactics to clean your email list

The best way to keep your email list clean is to implement best practices as your list grows. After all, 23% of email addresses change within a year, if your list is large that’s a lot of fluctuation to keep track of. Here are some practices to make things easier.

Scrub your email list with bulk verifications

The idea of bulk management isn't hard to wrap your brain around. In most tools, there is a capability to import addresses and generate a CSV or JSON file that can be sorted, analyzed, and optimized. 

Bulk verification tools use this functionality to allow businesses to scrub their lists according to parameters like looking for typos (think gnail vs gamil) and validating domains.

Identify non-engagers with reactivation campaigns

Before you delete unengaged users, create a strategy to try and keep them.

Reactivation (or re-engagement campaigns) are a last stitch effort before scrubbing these emails from your list. Before you remove an inactive address from your list forever, implement the practice of segmenting non-engagers and focus on encouraging new interaction with targeted campaigns and messaging.

Automate cleaning with sunset policies

A sunset policy is a plan to clean unresponsive or disengaged recipients from your email list by regularly reviewing your engagement metrics. When used with a reactivation strategy, sunset policies help curate a list of only engaged users.

Why do you need a sunset policy from a deliverability perspective? Well, it’s not enough for your recipients not to mark your emails as spam. Inbox providers also care if your recipients are interacting with your messages in a positive way by opening them and clicking through to your links. Engagement counts toward your overall sender reputation, so if recipients are not reading your emails, that will negative impact your overall deliverability.

Implement double opt-in

There’s no better way to ensure your recipient’s interest in your email communications than double opt-in. Double opt-in is a validation step that requires users to confirm they want to be added to your email list via a confirmation link sent to their submitted email address.

Double opt-in practices have become an industry standard, especially now in the age of rapidly emerging data privacy laws. You want to ensure the email addresses you collect were obtained with clear and well-documented consent.

Clean your list at point of signup

Validating addresses as they are captured is the quickest way to ensure clean email list building and a clean sender reputation. If you don’t catch them, invalid addresses can send you on a path of being blocklisted or snagged by spam traps.

Using an email validation service to check the accuracy of emails entered at sign-up allows incoming addresses to be checked for common mistakes and prevents invalid addresses from being added to your list in the first place. When used in tandem with practices like double opt-in, validation at sign-up is an easy way to implement list cleaning practices.

Use Mailgun’s email validation tool for bulk cleaning and list scrubbing to target invalid or spam email addresses from being added to your list at point of signup. Learn more here.

Email list cleaning services: 3 tested methods to scrub your email list

We’ve talked about what you need to keep your list clean. When it comes to selecting a tool there are three key things to look for.

Bulk verification capabilities

Bulk verification features look for fake emails and addresses with known spam complaints as well as checking syntax. This not only helps with engagement but reduces your bounce rate and increases your sender reputation.

You’ll notice bulk verifications was the first thing we mentioned in this post on our list of what you need to keep your list clean. That’s because you do not want to be in a position where you are manually going through to verify each address. You want to be able to validate these email addresses quickly with API support.

Compatibility with an email API

Here are two words not to forget when searching for a good tool: Instant verification. That’s what you’ll get with an email list cleaning software that is compatible with your email API.

APIs allow two applications to communicate with one another. With email verification tools, that connection is between the list cleaning application and the application you use to collect emails or manage your signup forms. When an email address is entered, you want the verification process to be instant to make sure the new emails are genuine and not disposable or temporary addresses, or spam addresses.

Integration support

Most organizations utilize tools from a variety of places. APIs are great for communicating between applications, Integrations are needed to connect to other tools, like CRMs, that you may be using to manage or acquire your contacts or support your sales team.

Your email program should be designed by you, and your tools should be able to work together even if they aren’t from the same product suite.

Clean your list with Mailgun’s email validations

Your contacts fuel your email communication strategy. A clean email list streamlines your efforts by removing the dead weight of invalid email addresses, and ensuring your contacts are being managed and monitored for engagement. Keeping your email list healthy may seem like a commonsense step, but even the simple things can be complicated and time-consuming.

Trust us, you don’t want to compromise your email program with a poorly managed list. Luckily, we can help make sure that doesn’t happen. Don’t be dirty, look into our solution to test the effectiveness of email validation for yourself and keep your email lists clean.

Email validations

Protect your business with email validations

Don’t let honeypots and spam traps make their way into your email list. Use Mailgun Optimize’s email validation service to protect your database at signup and to clean your list periodically.

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