List Hygiene

List hygiene is the routine work of keeping your email list clean: removing invalid addresses, hard bounces, duplicates, role addresses that nobody reads and contacts who have not engaged in a long time. A clean list is smaller, but more of it reaches real people who want your email.

Why it matters for a small business

Every bad address on your list costs you something. Hard bounces and spam traps damage your sender reputation. Inactive contacts drag down your open rates, which tells Gmail your email is not wanted. Many platforms also charge by contact count, so you may be paying every month to email people who will never read it.

What list hygiene includes

• Validating new addresses at signup so typos like gmial.com never get in.
• Removing hard bounces right away.
• Suppressing contacts who have not opened or clicked in six to twelve months, after a re-engagement attempt.
• Running older or imported lists through an email validation tool before sending.
• Merging duplicates so the same person does not get the same email twice.

A real-world example

A business imports 6,000 contacts from an old CRM to start a newsletter. Before sending, they run the list through a validation tool. About 900 addresses come back invalid or risky. Removing them before the first send avoids a bounce rate that would have flagged the domain on day one.

How often to do it

Validate at signup on an ongoing basis, clean bounces after every send and review inactive contacts every quarter. The best setup automates most of this so it does not depend on someone remembering.

Related reading: Validate before you automate and list health automation for dormant subscribers. We build list hygiene into our email automation and deliverability service.