Understanding Contacts in Mailchimp 

And How to Clean Inactive & Irrelevant Contacts to Keep Costs Down

For many businesses, Mailchimp is an incredibly powerful platform for email marketing — but also one that can become expensive if your contact list grows uncontrollably. What many users don't realize is that not all contacts in Mailchimp count the same, and keeping inactive or irrelevant contacts can significantly drive up your monthly cost without delivering any value.

As a Certified Mailchimp Expert and PRO Partner, I see this issue constantly: businesses are paying for contacts who haven't opened an email in years, or for leads they shouldn't keep at all.

In this guide, we'll walk through:

• The different types of contacts in Mailchimp

• Which contacts you actually pay for

• How to identify inactive or low-quality contacts

• How to clean your audience safely

• Automations that keep your list clean going forward

Let's dive in.

What Exactly Is a "Contact" in Mailchimp?

Mailchimp uses the word "contact" as an umbrella term for anyone stored in an audience — but not all contacts behave the same. Here's a quick breakdown:

1. Subscribed Contacts

These are the people actively receiving your campaigns.

- You pay for all subscribed contacts in your audience.

2. Unsubscribed Contacts

These people have chosen not to receive emails from you anymore.

- They still count toward your monthly bill unless you archive or delete them.

3. Non-Subscribed Contacts

These contacts come from e-commerce integrations or form submissions but haven't opted in to marketing.

- They do not receive campaigns but count toward your monthly plan.

4. Cleaned Contacts

These are email addresses Mailchimp has marked as hard-bounced or permanently unreachable.

- They don't count toward your billing — and you cannot email them.

5. Pending Contacts

These contacts opted in using 'double opt in', but the contact havn't confirmed the email yet.

- They don't count toward your billing — and you cannot email them.

The important takeaway:

If a contact is still in your audience and marked "unsubscribed" or "non-subscribed," there's a good chance you're paying for them even though you can't email them.

Why Cleaning Your Mailchimp Audience Matters

A messy list leads to:

• Higher monthly costs

• Lower open rates and click rates

• Poorer deliverability (hurts sender reputation)

• Inaccurate reporting

• Inefficient segmentation and automation

Plus, a clean list means your messages reach engaged subscribers — improving your ROI.

How to Identify Inactive Contacts in Mailchimp

Inactive contacts typically fall into one of these categories:

1. No Opens or Clicks in 6–12 Months

A standard benchmark. (For high-frequency senders, use 3–6 months.)

2. Contacts Who Never Engaged

They joined your list… and then ghosted you.

3. eCommerce Contacts Who Never Opted In

Useful for transactional emails but not for campaigns.

4. Unsubscribed Contacts

You can't email them anyway — so archiving them is usually safe.

5. Duplicate in multiple audiences or Mistyped Emails

These hurt your deliverability and inflate your bill.

Mailchimp's segment builder and contact ratings make it easy to surface these groups.

How to Clean Contacts in Mailchimp (Safely)

Cleaning doesn't have to be scary. The process can be done in three steps:

Step 1 — Segment Your Inactive Contacts

Create a segment such as:

• Campaign activity: did not open any emails in the last 180 days

• AND is subscribed

• AND was added more than 90 days ago

This avoids removing brand-new signups who haven't seen many campaigns yet.

Step 2 — Send a Re-Engagement Campaign ("The Last Call Email")

Before removing inactive contacts, give them a fair chance:

• Tell them you noticed they haven't interacted.

• Ask if they still want to receive your emails and present them with an offer they can't refuse.

• Use "Stay subscribed" vs. "Unsubscribe" CTA buttons.

• Only keep people who interact.

Mailchimp expert tip:

You can tag contacts who click any link in this campaign to keep them active.

Step 3 — Archive the Dead Weight

Archiving is reversible and does not delete historical data.

Archiving removes contacts from your billing without losing:

• Tags

• Segments

• Reports

• eCommerce history

It's the safest option if you're unsure.

Do not delete unless absolutely necessary (e.g., GDPR data deletion requests).

Bonus: Automate Your List Hygiene (Set it and Forget it)

Mailchimp doesn't have built-in auto-purge features, but you can set up systems that keep your list clean automatically:

1. Engagement Tagging Automation

Set an automation to apply tags like:

• Engaged – 30 days

• Engaged – 90 days

• Dormant – 180 days

Use these to trigger clean-up or re-engagement flows.

2. Auto-Tag New Subscribers Based on Source

Identify low-quality sources early (e.g., contests or giveaways).

3. Use Mailchimp's Contact Rating

Automatically suppress or archive 1-star contacts.

4. Connect eCommerce Platforms

Ensure unsubscribed or non-subscribed customers aren't stored as contacts in Mailchimp unless you need them for transactional emails like abandoned cart etc..

How Cleaning Your Audience Saves Money (Real Example)

A business with:

• 10,000 subscribed contacts

• 3,000 inactive contacts

• 2,000 unsubscribed contacts

…might be paying for 5,000+ contacts that bring zero value.

After archiving those contacts, monthly costs could drop by 30–50% instantly.

For many businesses, list cleaning pays for itself in one day.

When You Should Not Clean Certain Contacts

Don't remove contacts who:

• Are customers with purchase history (even if inactive)

• Are needed for abandoned cart or product follow-up automations

• Provide valuable data for segmentation or retargeting

Instead, tag them and keep them suppressed from marketing emails.

Final Thoughts: A Clean Mailchimp List = Better Deliverability + Lower Costs

Understanding how contacts work in Mailchimp is essential for controlling costs and improving your performance. With regular maintenance — or with automated tagging workflows — you can:

• Lower your monthly Mailchimp bill

• Improve engagement & deliverability

• Keep your audience relevant and high-quality

• Protect your sender reputation

A small investment of time leads to major long-term gains.

Need help Cleaning your Mailchimp Audience?

More insights from a Mailchimp Expert