Mailchimp IP Ranges

Currently, Spambrella only supports up to /24 CIDR ranges. However, some third party services such as MailChimp use larger ranges than we support. In these cases, you will need to break up the bigger CIDR ranges into /24 ranges before adding them to your Safe Sender List. You can find the full broken down IP range at the bottom of this FAQ.

As an alternative to adding the above IP range, you can create a custom filter:

To create the Mail Chimp filter you will need two key pieces of information:

From Address – Obtained From the details window of a Mail Chimp email
x-MC-User ID – Obtained from a Mail Chip MessageID

You can now create the following filter:

IfSender address is From Address

AndHeaders Contains x-MC-User ID

Click – Allow

Based on the analysis of various emails from Mailchimp it has come to our attention the x-MC-User ID string is unique to each mail chimp ‘tenant/account’ so this filter should white list emails from mail chimp while retaining tighter security than whitelisting the entire IP range (below)…

Broken down range for Mailchimp: