Note: if you need a complete WHMCS addon module for Mailchimp integration where customers can subscribe to lists and interest groups of their choice, see ezchimp
Subscribe your clients in WHMCS to required mailing list and interest groups in your MailChimp account based on the product group they order.
Suppose you want to auto subscribe your client to “Hosting” interest group in your MailChimp mailing list when they order one of your “Web Hosting” product and to “Domains” interest group when they purchase one of your “Domain” product, this script can do it for you. You can organize your clients to different interest groups easily and send newsletters and special offers to specific interest groups for maximum effective email marketing.
This script makes use of WHMCS AcceptOrder hook and WHMCS and MailChimp APIs.
Thanks to Juan Manuel Zolezzi Volpi, Duplika Internet Solutions for the idea and funding for the development of this script and permission to share it.
Steps to setup:
- Set values for config variables and WHMCS product group to MailChimp mailing list and interest groups map
- Upload this script to includes/hooks folder inside your WHMCS install folder
- Make sure the merge fields in mailchimp mailing list are set as:
- Test by accepting an order
For setup assistance, customizations or consultation, contact support[at]admod.com

Greetings, is this compatible with 4.5.2 WHMCS ? if so i tried it and it does not seem to be working… any tips ?
Thanks
Hi Mitch,
Yes. Is there any errors? Please send a mail to support[at]admod.com with details. We shall have a look.
What happens if a client changes their email address in WHMCS? Does Mailchimp get updated too?
No, it will have to be handled separately.
Would be nice if it ran a sync on a cron run or something maybe this can be a future update ?…. on another not i was wondering if its possible to add functionality to manually subscribe existing users… via a button or something…… This would be neat and easy to manually add people not just new clients… Any chance ?
Great ideas Mitch, shall look into implementing these. If you wish to get customizations or new features implemented quickly, you may contact sales [at] admod.com
Is the script listed here still the latest version?
The changes that mitch mentioned sounded nice.
Yes, it is the latest. Mitch’s suggestions could not be incorporated into this script. So we are writing a separate WHMCS module for MailChimp newsletter management – ezchimp. Development has been completed. Testing documentation etc in progress. Follow http://twitter.com/ezchimp for updates.
Awesome!
Thanks.
Has development on ezchimp died out? The Twitter account seems dead and it doesn’t look like there have been any updates for quite some time.
Wondering if the version that is provided here is compatible with latest WHMCS version and current Mailchimp API.
I’m also looking for the automatic “add to mailing list” upon product purchase feature, which sounds like it never got out of beta.