What Is Email List Hygiene?

Email list hygiene (also known as list cleaning and list scrubbing) is the process used to review and update your email recipient list to ensure that your emails are not being sent to email addresses that will bounce or mark your message as spam. Monitoring and maintaining a healthy marketing email list is critical for maintaining a high email deliverability status and sender reputation.

Every company's process for list hygiene is different, but the ultimate goal is the same: Only send messages to recipients who want to receive them. That means ensuring those recipients will engage with the content of the email you send.

Benefits of List Hygiene

Increased email deliverability
Higher open/engagement rates
Minimized spam complaints
Improved sender reputation

Impact of Not Cleaning Your List

Your email deliverability and reputation can and will be directly impacted by failing to clean your email list through either non-engaged users or problematic email addresses.

Non-engaged Users

Non-engaged users are recipient addresses that are not interested in your content/message and should be removed from your list immediately to improve delivery rates. Examples include:

Inactive/abandoned: Users that have not opened any received emails over a period of time (e.g., 6 months).
Non-segmented: Recipients are not the target audience for the delivered message.
Unsubscribe requests: Recipients decline to receive future emails from your domain. Click here for more details.
Role-based emails (distribution lists): Sent to a specific role or department in an organization instead of a specific person (e.g., admin@, support@, legal@, sales@). Non-transactional emails such as these are less likely to be engaged, so segmenting is key.

Problematic Email Addresses

Problematic email addresses are difficult to deliver to or have been used for spam, which can harm your deliverability. Some common examples are:

Invalid and bouncing email addresses: Incorrect formatting, typos, full mailbox, missing domain, hard/permanent bounces
Spam traps/honeypot addresses: Marking/labeling delivered emails as spam and not actively used by individuals
Disposable/temporary addresses: Expires after a certain time frame and not used as a primary email address (e.g., listhygiene9876@hotmail.com)

By deleting any inactive subscribers, invalid email addresses, spam traps, and uninterested contacts from your marketing campaigns, you ensure only engaged customers receive your messages.

How to Improve Your List Hygiene

After doing an initial list cleaning/scrubbing, you can utilize these best practices to continuously maintain a healthy list:

Use double opt-in: Adopt this practice to ensure active customers consent to receiving your emails. (For more double opt-in information, click here.)
Monitor engagement data: Review your marketing campaign data to identify engaged/unengaged contacts to help maintain optimal list hygiene.
Segment your marketing list: Categorize your subscribers by various factors (demographics, interests, behaviors, etc.) to send targeted messages to specific audiences.
Routinely scrub your email list: Remove all inactive, unengaged, and bounced contacts to create good list hygiene.