Overcoming the MailChimp Omnivore warning

Omnivore warning

MailChimp is among the top Email Service Providers (ESPs) worldwide. They send over fifteen billion emails monthly. Omnivore is MailChimp’s abuse prevention system and the most effective abuse prevention system in the world.

MailChimp has widely been cited as the topmost contender in terms of best emailing practices.

Omnivore has a reputation for being strict and has in the past identified thousands of accounts as malicious. It has even prevented numerous emails from being sent. They may be millions or billions in number.

Since MailChimp Omnivore is an AI-powered system, it has a margin of error. There are cases wherein legitimate accounts are also flagged for being false positives. So what is it that one can do to prevent his email campaigns from being flagged, which may lead to a possible suspension of his account?

…Algorithmic email abuse systems have a scope for error since legitimate accounts are occasionally flagged…Upon receiving three flags in six months, one faces permanent account removal.

If a MailChimp user receives a MailChimp Omnivore warning, it does not imply a MailChimp account suspension. It instead implies that one can no longer send emails to flagged lists.

But sending out emails to non-flagged lists is still permitted. One can create campaigns, but one has to see that the list he has created or imported for sending emails is not flagged.

Let us take a closer look at what the warning implies. Whenever a user imports a list that has been newly created, the list is scanned and analyzed by MailChimp Omnivore. This is over parameters such as abuse complaint addresses, hard bounce, and spam traps.

Upon passing a certain threshold, which MailChimp does not specify, sending to that particular list is suspended. MailChimp then prompts a user to remove the offending list and try again following a few cleanups.

But a user has to remember that if his account is flagged thrice in six months, it will permanently be closed.

So why is MailChimp so aggressive? It’s because they are proactively safeguarding their IP reputation. Spammy accounts tend to affect that reputation.

Cleanup options


A factor that frequently doesn’t work well for email marketing lists is bad email syntax. This could spell doom for your IP sender reputation. The odds of the same enhance significantly when one uses single opt-in processes or forms.

The list of most commonplace email addresses errors:

  • email ids with the missing @
  • emails with additional spaces
  • ids with the missing dot

Purchased lists are more likely to have bad email addresses in more numbers. When one passes such lists through MailChimp, it boosts the odds of the list getting suspended and your account being flagged.

A user should manually scan his email list in Excel, before passing it through MailChimp. For the same, download your email list in an Excel spreadsheet. Then use the following formula in the cells.

=AND(FIND(“@”,A2),FIND(“.”,A2),ISERROR(FIND(” “,A2)))

While this formula will identify some bad email ids in your list, it does not validate the list. Even while a list does not have syntax errors, it may still have abandoned and junk addresses.

To avoid MailChimp Omnivore, there is thankfully one way that is reasonably inexpensive while being quick and reliable. A user can avail of one of the accurate email services, such as Email List Validation. This will delete the bad email ids in your list.

The following is a list of a few of the bad address types that email checker will identify and differentiate from your list:

  • Emails which hard bounce
  • Emails that have typos
  • Emails including invalid MX records
  • Emails with syntax errors
  • Temporary or disposable ids
  • Role-based emails, like [email protected] and [email protected]

NOTE: We do not personally recommend purchased lists. They are more likely to have excessive errors and invalid emails. There would be others like you who’ll be using this list. Since MailChimp sends 15 billion emails monthly, MailChimp Omnivore will be familiar with the list that you intend to purchase.

Email verification by Email List Validation is commendable for being precise and trustworthy. Just as an example, a few email types require complex software to be checked. Upon using Email List Validation, accuracy exceeds 98%.

By using email validation services, a user reliably eliminates the vast majority of Omnivore warning triggers. Omnivore and MailChimp do not disclose the emails that are flagged or ways in which they should be removed. After Omnivivore flags a user’s list, it is entirely up to him to sanitize and clean the same.

A user should still make sure that he does not blindly delete any potentially valid emails. This may result in loss of leads or sales.

Some important points regarding Omnivore

omnivore mailchimp

MailChimp Omnivore is exceedingly useful as a tool. We overcome spam owing to Omnivore. But for a MailChimp user, getting caught in the Omnivore’s net is complicated. Therefore, a MailChimp user should also use a service such as Email List Validation. A user is unlikely to be amused by running through email ids, thousands, or millions in number. It is further difficult to verify the valid email ids. Manual cleanup is unlikely to be as effective as email validation.

Is MailChimp going to help you with the Omnivore warning? You can always try, but the support is not guaranteed. It is henceforth important that a user stays proactive regarding his email list’s health, right from the beginning.

For eliminating the majority of Omnivore warning triggers, a bulk email verifier service is the most effective tool.

Additionally, Email List Validation is highly affordable (They offer a Freemium account with 100 free yearly credits as well). This comes along with the official MailChimp Integration.

Overall, Email List Validation is the prime alternative for cleaning your list in entirety. But we still can’t guarantee that you’ll get across Omnivore. This is because MailChimp does not inform regarding any dimensions of Omnivore’s findings.  Correspondingly, there is no sure shot way which prevents a list from being flagged. There are merely ways to reduce the odds of the same happening.