Email Glossary

List Hygiene

List hygiene refers to the ongoing practice of maintaining a clean, healthy email list. This includes removing invalid addresses, unengaged subscribers, spam traps, and duplicates to improve deliverability and engagement rates.

Why List Hygiene Matters

A dirty list hurts you in multiple ways:

Deliverability impact:

  • ●High bounces damage sender reputation
  • ●Spam traps can get you blacklisted
  • ●Low engagement signals to ISPs that you're spammy

Cost impact:

  • ●Paying for contacts who never open
  • ●Wasted sends on invalid addresses
  • ●Higher bounce processing costs

Metric distortion:

  • ●Open rates artificially low
  • ●Can't identify what's actually working
  • ●False sense of list size

What to Remove

Hard bounces: Remove immediately after first bounce. These are permanently invalid.

Soft bounces: Remove after 3-5 consecutive bounces. May indicate abandoned mailbox.

Spam complainers: Remove and suppress immediately. Never email them again.

Long-term inactive: After 6-12 months of no opens, try re-engagement then remove.

Role addresses: info@, support@, sales@ often aren't read by individuals.

Spam traps: You won't know until you're blacklisted. Validation services can help identify likely traps.

Hygiene Process

Regular maintenance (ongoing):

  • ●Process bounces automatically
  • ●Honor unsubscribes immediately
  • ●Monitor engagement metrics

Periodic deep clean (quarterly):

  • ●Run list through validation service
  • ●Identify and remove inactive subscribers
  • ●Deduplicate across lists

Before major campaigns:

  • ●Validate any recently imported lists
  • ●Use engaged lists
  • ●Consider re-verification for old addresses

Re-engagement Campaigns

Before removing inactive subscribers, try to win them back:

Email 1: "We miss you" - Remind them why they signed up Email 2: "Last chance" - Clear warning you'll remove them Email 3: "Goodbye" - Final notice, link to re-subscribe

Those who engage stay. Those who don't get removed. This approach:

  • ●Recovers some valuable subscribers
  • ●Gives fair warning
  • ●Documents your intent for compliance

Related Terms

Bounce Rate

The percentage of sent emails that couldn't be delivered to the recipient.

Email Deliverability

The ability of your emails to reach recipients' inboxes instead of spam.

Sender Reputation

A score ISPs assign to your sending IP and domain based on email behavior.

Frequently Asked Questions

How often should I clean my list?
Process bounces and complaints automatically (real-time). Do a deep clean quarterly. Before major campaigns or after not sending for a while, validate the list. The more you send, the more hygiene matters.
Should I delete or suppress removed contacts?
Suppress, don't delete. Keep a suppression list of addresses you should never email again (complainers, hard bounces, unsubscribes). This prevents accidentally re-adding them later from other sources.
Is it worth paying for email validation?
Yes, especially for older lists, imported lists, or before major campaigns. Validation catches invalid syntax, defunct domains, known spam traps, and disposable addresses. The cost is less than the reputation damage from bounces.
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