Why did Mailchimp send my email to fewer people than are in my audience?
The Mailchimp help pages give 5 common reasons. The first to rule out: People who unsubscribe stay in your audience but no longer get your marketing emails, so the number sent can be lower than the number of contacts.
Is it broken, or just quiet?
A number can fall because fewer people came, or because something stopped counting them. Below are the causes the Mailchimp help pages give, and how to check each one yourself.
What causes it?
People who unsubscribe stay in your audience but no longer get your marketing emails, so the number sent can be lower than the number of contacts.
In the Mailchimp help:
When a contact unsubscribes from an audience, they opt out of marketing emails and SMS messages for that audience only.
About Unsubscribes, read 2026-11-12.Contacts who never subscribed to marketing can still be in your audience without receiving your marketing emails.
In the Mailchimp help:
Can't receive: Marketing emails, marketing text messages
About Your Contacts, read 2026-11-12.Mailchimp marks addresses that keep bouncing as cleaned, which can lower the number of people a campaign goes to.
In the Mailchimp help:
Cleaned contacts have email addresses that have hard bounced or repeatedly soft bounced, and are considered invalid.
About Cleaned Contacts, read 2026-11-12.Once an address is cleaned, later campaigns skip it, so a run of bounces can make your next sends smaller.
In the Mailchimp help:
Cleaned addresses can't receive future emails you send to your audience.
About Cleaned Contacts, read 2026-11-12.Archived contacts are kept out of your campaigns until they are brought back.
In the Mailchimp help:
As long as a contact remains archived, you won’t be able to edit their profile or send them any marketing communications.
About Your Contacts, read 2026-11-12.
How do I check it myself?
Compare the recipients number in the campaign's report with your audience size to see how many contacts were left out.
In the Mailchimp help:
The number of contacts the email was sent to.
About Email Reports, read 2026-11-12.Make a segment of unsubscribed contacts to see how many people in your audience no longer get your campaigns.
In the Mailchimp help:
To view your unsubscribed contacts, you will create a segment of them in your audience.
View Unsubscribed Contacts, read 2026-11-12.Compare recipients with successful deliveries in the report to see how many addresses bounced, since those can be cleaned later.
In the Mailchimp help:
The number of recipients who didn't hard or soft bounce on this email.
About Email Reports, read 2026-11-12.
How would I know the day it starts?
- Feder reads the campaign emails Mailchimp sent each day and compares each day with your own history.
- It does not read your audience size. It tells you when emails sent go quiet or move outside their usual range.
Some numbers are too quiet to judge daily, such as a form filled in a few times a week. Until there is enough of your own history to judge a change, Feder says it is still learning and scores nothing, rather than guessing.
See what Feder reads from Mailchimp, which feeds Reach. Feder only reads. It never changes anything in Mailchimp.
What else goes wrong with these numbers?
- Why do my Mailchimp email clicks look wrong?Mailchimp
- Why did my Mailchimp open rate jump?Mailchimp
- Why did Google Analytics stop collecting data?Google Analytics
- Why aren't my key events showing in Google Analytics?Google Analytics
- Why does Google Analytics show (not set)?Google Analytics
See every question.
Where do these answers come from?
Every cause and check on this page comes from the Mailchimp help pages, quoted above with the date we read them. Last reviewed 2026-11-12. We read them again by 2027-11-12. If one changes, this page changes or comes down.