Configuring MailChimp to make it work with Impact Stack

The following is valid for all Impact Stack Out-of-the-Box installations. If you have a customised version, there may be slight differences. Feel free to ask support if in doubt!

Please be aware that for syncing of Impact Stack data with a Mailchimp list to work, the supporter needs to have an email opt-in activated for that list either through an Impact Stack webform or already saved in the Impact Stack supporter database.

Adding merge fields step-by-step

We will take the example of the tags field :)

  1. open the list(s) you'll be using in MailChimp
  2. go to Settings --> "List fields and *|MERGE|* tags"
  3. scroll to bottom --> "Add a field"
  4. choose type "text"
  5. name it "Tags"
  6. replace the merge "MMERGE1" (the number after the MMERGE can vary) with "TAGS"
  7. Save the changes


Repeat these steps for all the fields you need. The available merge fields are listed below.

Impact Stack offers the following standard merge fields:

  • EMAIL   --> a text field for the email address
  • FNAME   --> a text field for first name
  • LNAME   --> a text field for last name
  • SALUTATION  --> a text field with Mr, Mrs, Ms, ...
  • TITLE      --> a text field with Dr., Prof, ...
  • GENDER   --> a text field with m or f
  • DOB      --> either a text field or a birthday field for the date of birth
  • COUNTRY  --> a text field for a country chosen in the corresponding form field
  • ZIP       --> a text field with zip code / post code
  • CITY     --> might also be a village ;-P
  • REGION   --> or State, or devolved country
  • STREET   --> for the Street / Address1 field
  • CREATED  --> a date field or a text field recording when this supporter record was created first in Impact Stack
  • UPDATED  --> a date field or a text field recording when this supporter record was last updated
  • TAGS   --> a text field for the auto-segmentation tags added to online actions, to avoid confusion with the now available native Mailchimp tags, you might want to set a label like "Impact Stack tags", however for the merge tag itself, please use the uppercase "TAGS".

On request, some additional merge fields can be available under some conditions (supporters with a postcode in the UK, "Email to Target" feature activated with access to the MP dataset and you asked support for the activation):

  • MP_CONST --> the constituency of the supporter's MP
  • MP_PARTY --> the party of the supporter's MP
  • MP_NAME --> the name of the supporter's MP
  • DVCOUNTRY --> devolved country of the supporter's MP, ie. England, Wales,...

It should then look something like this:

Adding your own fields to MailChimp

Apart from the standard fields listed above you can add any of your custom fields from your Impact Stack webform by adding the Impact Stack form key in the MailChimp merge field.

Subscribe your supporters to MailChimp Interest Groups

If you are using Interest Groups, you can set up your opt ins on your Impact Stack forms to add subscribers to those groups - you’ll need to ask support to enable the MailChimp Interest Groups module for you.

Once that’s done, you’ll see an additional ‘Groups’ tab in the configuration options of the opt in field, which will list all the MailChimp Interest Groups available in your account. You can use this tab to select which groups you would like to add subscribers to. (It will list ALL the available Groups in your MailChimp account, so make sure that you have also selected the correct List in the Lists tab; the supporter will only be added to the Interest Group if they are also subscribed to the relevant List.)

This means you can, if you want, have multiple opt ins on your page, which subscribe people to different MailChimp lists and/or groups.

Multiple opt-in components/form elements with distinct lists are each taken into account separately.

If two (or more) components have overlapping lists then subscribes take precedence over unsubscribes. For example if you set up two fields linked to the same list but with different Interest Groups, with No=unsubscribe, and the user said Yes to the first and No to the second, then the user would be subscribed to the list with the Interest Group from the first. (Both responses will be recorded individually in the opt-in/opt-out export.)

Bear in mind that unsubscribes are always per list; they ignore the group setting. So if the user in the scenario above was already on that list with the second Interest Group, and picked 'No' on that second newsletter field, they would not be removed from that Interest Group.

Mailchimp GDPR fields

Mailchimp offers 'GDPR fields', which are designed to support users to collect GDPR compliant opt-ins through Mailchimp sign up forms. Read more about the feature.

Impact Stack doesn’t integrate with the Mailchimp GDPR field functionality because you set up your opt in on the Impact Stack form.

If you have GDPR fields enabled in your Mailchimp, contacts that are added to your audience via Impact Stack will show up in the activity feed as having “Opted-out of email” (and any of the other channels set up in the GDPR field settings in Mailchimp). But rest assured, your supporters will still be subscribed if they have opted in via Impact Stack.

There's no need to disable the fields, just keep your setup as it is - Impact Stack will not overwrite consent given for GDPR fields if supporters have previously opted in. If you're not using any Mailchimp sign up forms though, and your sign ups are all coming via Impact Stack, you can turn this feature off.

Of course you need to configure your Impact Stack forms correctly to collect GDPR compliant opt-ins. More information on how to set up opt-ins in Impact Stack.

For further information on MailChimp please refer to their really helpful documentation:

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