Increasing Open Rates Starts With Better Lists

TL;DR

• Delete any list or segment if you cannot explain what it is for

• Archive tags and audiences that are more than six months old and not tied to automation

• Rebuild campaign sends from current CRM fields and behaviours, not old imports

• Better list hygiene leads to higher engagement and fewer internal errors

You log in to Mailchimp. Or Pardot. Or Campaign Monitor. There are dozens of lists, tags, segments, and audiences. Some were uploaded for a single campaign. Some were duplicated. Some are called things like “March Send - Final Final.”

No one knows which one to use. So someone picks one that looks close enough, changes the name, hits send, and hopes for the best.

This is not laziness. It is survival. Marketing teams are under pressure to get emails out quickly. The longer term result is low engagement, high internal risk, and a growing sense of unease every time you open the platform.

Eventually, no one trusts the data, and the entire process becomes fragile.

1. Lists That Should Not Exist

The Problem:

Marketing platforms fill up with lists that were uploaded quickly and never used again. These lists live on, unnamed in automations or reused by mistake.

Why It Happens:

Speed. A campaign needed to go out. A spreadsheet was uploaded. The list worked. No one followed up.

What To Do:

• Delete any list not actively used in a campaign or automation

• If you cannot explain what a list is for, delete it

• Remove uploaded lists within one week unless they are explicitly reused

Crinkle Cut Rule: Delete first, ask questions later. If it matters, someone will tell you.

2. Tags and Segments That No Longer Mean Anything

The Problem:

You have segments based on fields that no longer update, or tags that were added during imports but never cleaned up. You see labels like “Engaged?”, “Prospect – Aug,” or “Webinar Target 2021.”

Why It Happens:

Every upload gives you the option to tag. So people do. But over time, no one checks which tags are actually in use.

What To Do:

• Audit your tags and group them by purpose

• Delete or archive any tag older than six months unless it is tied to automation

• Agree on a team-wide tagging convention (e.g. behaviour-based tags only)

Example: Use “Clicked – Webinar Invite” or “Attended – VIC Briefing,” not vague labels like “Engaged”

3. Lists Without Owners

The Problem:

You find a list called “HNW Q3 Targets FINAL V2.” No one knows who created it. Everyone is afraid to delete it in case it is used somewhere.

Why It Matters:

Unowned lists are risky. They get reused incorrectly, excluded from key campaigns, or left connected to automations that no longer make sense.

What To Do:

• Include owner initials and a “last reviewed” date in every list or segment description

• If no one claims ownership, archive or delete it

• Introduce a policy: if it is not owned, it is not used

4. “Just Send It” Logic

The Problem:

Instead of building a fresh audience, someone copies a past segment, renames it, and launches the next send.

Why It Happens:

Getting the email out is prioritised over verifying who is actually receiving it. This is common, but it builds technical debt and undermines results.

What To Do:

• Add a step to your QA checklist: validate the list logic

• Ask: Is this list current? Is it linked to meaningful behaviour or CRM fields?

• If in doubt, rebuild the list from known-good filters and data

Reminder: A clean message sent to the wrong people is still a bad campaign

5. Waiting for AI Will Not Help

The Problem:

Some teams hope that AI-driven segmentation will clean things up—smarter targeting, better suggestions, more automation.

Why It Matters:

No model can fix bad tags, inconsistent field use, or historical clutter. This is a people problem, not a tooling problem.

What To Do:

• Set aside time for a clean-up sprint

• Remove anything that is ambiguous or outdated

• Rebuild a small set of core segments from behaviour-based data, not past campaign artefacts

  
  

The Goal: Create a system you understand and can explain, without second guessing

Final Thought

List management is not admin. It is the foundation of email performance.

If engagement is low, the problem may not be timing, creative, or subject lines—it may be who you are sending to. Or who you are missing.

Cleaning your lists, tags, and segments reduces internal confusion, improves targeting, and increases trust in your tools.

If you feel anxious when you log in to your marketing platform, your list hygiene is part of the problem.

Fix that, and your open rates will follow.