Mailchimp Changelog

5.4.0 | 2024-04-17

  • Fixed an issue where the status of an existing subscribed list/audience member changes to pending when double opt-in is enabled on the feed.
  • Reminder: The gform_mailchimp_args_pre_subscribe filter is deprecated and will be removed in a future version. Please use the gform_mailchimp_subscription filter instead.

5.3.0 | 2024-02-29

  • Updated feed processing to include the tags in the request to the add/update member endpoint instead of making a separate request to the member tags endpoint.
  • Fixed an issue where an "Unable to add/update subscriber: Invalid Resource" error occurs when mapped field values include HTML entities.
  • Fixed a Using ${var} in strings is deprecated, use {$var} instead deprecation notice with PHP 8.2.
  • Fixed an error where the Mailchimp connection alerts appear when attempting to connect other add-ons.

5.2 | 2023-02-15

  • Added Gravity Forms license key to oAuth process.
  • Added support for async (background) feed processing to improve form submission performance.
  • Fixed an issue that prevents the Marketing Permission setting from being applied to users in certain situations.
  • Fixed an issue where the opt-in email is not sending to already pending members when they resubscribe.

5.1 | 2022-05-11

  • Fixed an issue where the save settings button isn't visible when creating or editing a feed.
  • Fixed a display issue with some conditional logic feed settings.
  • Fixed an issue where API calls are being made on all admin pages when checking for deprecated keys.

5.0 | 2021-09-29

  • Updated the authorization flow to connect to the Mailchimp API via Oauth.

4.9 | 2021-04-28

  • Fixed an issue where conditional logic is not correctly identifying matching selections when forms contain a multi-select field.
  • Fixed an issue where the add-on icon is missing on the form settings screen in Gravity Forms 2.5.

4.8 | 2020-09-09

  • Added support for Gravity Forms 2.5.
  • Fixed birthday merge fields no longer being sent in the correct format expected by the Mailchimp API.

4.7 | 2020-03-24

  • Added translations for Hebrew, Hindi, Japanese, and Turkish.
  • Added support for feed duplication.
  • Updated stylesheets to use minified versions.
  • Updated strings containing MailChimp to Mailchimp and list(s) to audience(s).
  • Fixed a PHP error which could occur when using the http_request_timeout filter with WP 5.1+.

4.6 | 2019-03-22

  • Added support for Marketing Permissions (GDPR) fields.

4.5 | 2018-12-19

  • Fixed new tags not being added when updating existing list member.

4.4 | 2018-10-29

  • Added support for MailChimp contact tags.

4.3 | 2018-03-27

  • Added security enhancements.
  • Added GPL to plugin header.
  • Updated API library to public property in support of MailChimp block.
  • Updated Plugin URI and Author URI to use https.
  • Fixed the MailChimp API returning a validation error for list date fields set to the DD/MM/YYYY format.
  • Fixed existing member retaining a status of cleaned or transactional instead of changing to pending or subscribed.
  • Fixed birthday and date merge fields not being sent in the defined date format.
  • Fixed an issue with the member status on resubscription to the list.
  • Fixed PHP notice if the interests are not returned by the MailChimp API for the existing member.
  • Fixed issue with css file that was being enqueued in every page.

4.2 | 2017-04-03

  • Added additional logging when checking if a user's subscription status.
  • Added existing member object as sixth parameter of gform_mailchimp_subscription filter.
  • Fixed PHP warning when attempting to check for existing interests when member did not belong to any interest categories.
  • Fixed Fatal error that happened in certain situations.
  • Fixed existing interest categories not being properly associated to subscription object.
  • Fixed an issue with subscriptions not being created due to empty merge fields.
  • Fixed an issue which could prevent the feed groups being converted to interest categories when upgrading from older versions of the add-on.
  • Fixed inability to use double opt-in with existing members.
  • Fixed API response error handling; API key was incorrectly shown as valid when a 403 Forbidden error was returned.
  • Fixed an issue with the field value used for interest category logic evaluation.
  • Restored GFMailChimp::get_group_setting_key() for use when upgrading from older versions of MailChimp Add-On.
  • Restored double opt-in support for members who are being resubscribed to a list they are unsubscribed from.
  • Disabled double opt-in support for members who are being resubscribed to a list they are unsubscribed from. (Member will be automatically subscribed to the list. This is a temporary workaround for an issue with the MailChimp API.)
  • Re-introduced support for gform_mailchimp_keep_existing_groups filter.

4.1 | 2017-01-03

  • Added additional error logging when creating a subscription.
  • Added support for configuring a note to be added to the subscriber.
  • Fixed a fatal error during feed processing when a list field is mapped to an entry property.
  • Fixed an issue where an Invalid Resource error would occur if the subscribers merge_fields property was included in the request when empty.
  • Fixed an issue with the note being urlencoded during merge tag processing.
  • Fixed users not being subscribed due to incorrect address formatting.
  • Increased number of merge fields returned for a list.
  • Updated feed processing to bypass override empty fields check for address fields.
  • Updated maximum number of category interests returned by the API.
  • Updated maximum number of interest groups returned by API.
  • Updated merge fields field map to only allow Address fields to be mapped to MailChimp address merge fields.
  • Updated strings for translations.
  • Updated subscription object to use existing member status where possible.

4.0 | 2016-12-20

  • Added gform_mailchimp_subscription filter to modify subscription object.
  • Removed 3.0 upgrade page.
  • Removed send welcome email as feed settings option.
  • Updated API requests to use MailChimp API 3.0.

3.7.5 | 2016-11-29

  • Fixed strings for translations.

3.7.4 | 2016-09-16

  • Fixed an issue with multi-input fields available for use with groups logic not including the inputs (i.e. Name and Address).

3.7.3 | 2016-05-06

  • Updated the MailChimp API to support the WP_PROXY_HOST and WP_PROXY_PORT constants when configuring the cURL options.

3.7.2 | 2016-03-11

  • Fixed an issue which was preventing feed processing aborting early if there is an issue with the MailChimp API.

3.7.1 | 2015-09-23

  • Fixed an issue where the cached settings were not cleared when the add-on was uninstalled.
  • Fixed a rare issue for some server environments where several groups could be assigned the same settings key causing js issues in the feed editor.
  • Fixed an issue where the cached group setting keys could be lost when updating the API key on the plugin settings tab.

3.7 | 2015-08-24

  • Added form and field specific versions of the gform_mailchimp_field_value filter.
  • Added logging of group condition evaluation.
  • Added $transaction, either Update or Subscribe, as the fifth parameter of the gform_mailchimp_args_pre_subscribe filter.
  • Updated minimum Gravity Forms version to 1.9.3.
  • Updated 'Opt-In Condition' setting label to 'Conditional Logic'.
  • Updated feed processing to use get_field_value() when retrieving mapped field values, enabling support for GF_Field::get_value_export with GF and later.
  • Updated to use GF_Field::is_conditional_logic_supported to determine which field types should be listed in the group condition fields drop down.
  • Fixed an issue with the feed list page if the API key not valid.
  • Fixed an issue with the location of the gform_mailchimp_args_pre_subscribe filter.
  • Fixed an issue with the upgrade routine which caused it run even if a pre-framework version hadn't been installed.
  • Remove plugin settings header and add line break after plugin settings description.

3.6 | 2015-04-20

  • Added filter to allow changing parameters to the API method that returns the MailChimp Lists.
  • Added Spanish (es_ES) translation.
  • Fixed a low severity security vulnerability in the admin area which could be exploited by authenticated users with form administration permissions.
  • Fixed an issue with the members existing groups being lost if no new groups were selected and gform_mailchimp_keep_existing_groups is true.

3.5 | 2015-02-03

  • Updated required version of Gravity Forms to 1.8.17.
  • Fixed an issue with Address fields where MailChimp would ignore the passed string if it did not contain the street address, city, state, or zip.

3.4 | 2015-02-02

  • Added support for the middle name input when preparing Name field values.
  • Updated required version of Gravity Forms to 1.9.
  • Fixed an issue causing checkbox fields not to be mapped under certain conditions.
  • Fixed fatal error with PHP < 5.4.

3.3 | 2015-01-30

  • Updated logging statements.
  • Updated the gform_mailchimp_field_value filter to have an additional parameter which includes the name of the custom mapped field.
  • Fixed issue causing address not to be mapped properly under certain scenarios.
  • Fixed Notice.
  • Fixed an issue with the concatenated string for Checkbox fields not being cleared before the next field is processed.
  • Fixed a warning when MailChimp interest groups aren't enabled on the list.

3.2 | 2014-12-08

  • Added hook to allow args to be changed before sending submission to MailChimp. add_filter( 'gform_mailchimp_args_pre_subscribe', 'override_mailchimp_params', 10, 4 ); function override_mailchimp_params( $params, $form, $entry, $feed ) { // do stuff

        return $params;
  • Added hook to select whether empty mapped fields should override existing values on Mailchimp; defaults to override. add_filter('gform_mailchimp_override_empty_fields', '__return_false' );

  • Fixed issue where existing groups were not maintained for users already subscribed.
  • Fixed notice messages.
  • Fixed fatal error displayed on certain situations.

3.1 | 2014-11-21

  • Fixed issue where grouping assignment was not working for already subscribed users.
  • Fixed issue where a fatal error is displayed in certain situations.
  • Fixed issue with upgrade that caused configuration not to be copied over in certain situations.

3.0 | 2014-11-04

  • Added integration with Add-On Framework.
  • Added support for sending selected checkboxes as a concatenated string.
  • Updated POT file.
  • Updated required version of Gravity Forms to 1.8.17.
  • Updated to MailChimp API version 2.0.
  • Updated files removing closing php tag at the end.
  • Fixed a warning when MailChimp interest groups aren't enabled on the list.

2.2 | 2013-06-19

  • Updated phone number when set to standard format "(#########)######### - ############" to send in required format of #########-#########-############.

2.1 | 2013-03-26

  • Added Name (Full) as an option to the field mapping list when the form has a Name field set to Normal or Extended format.

2.0 | 2013-03-07

  • Fixed PHP warnings when no API key was set.
  • Added the gform_mailchimp_field_value filter to enable the value to be modified before being sent to the MailChimp API.
  • Added entry meta to the list of available field mappings.
  • Fixed issue with group conditional logic not displaying all possible operators and value drop down correctly.
  • Fixed issue with special character in main group name.
  • Fixed issue with group conditional logic with non-selection field types.
  • Added new hook gform_mailchimp_allow_resubscription which allows disabling support for resubscription. add_filter('gform_mailchimp_allow_resubscription', '__return_false()');
  • Fixed issue saving group settings in admin when sub groups have the same name.

1.9 | 2012-11-28

  • Updated Group logic to keep existing groups.
  • Added filter to change logic back to overriding groups. add_filter("gform_mailchimp_keep_existing_groups", "__return_false");
  • Updated to treat members as if they were a new subscribe request when currently set to a status on MailChimp's side of unsubscribed, pending, cleaned.
  • Fixed issue with special characters in MailChimp Group names causing issues when creating feed.

1.8 | 2012-10-24

  • Fixed issue with GetFieldValues() when used with groups; was returning full select when only options were required.
  • Fixed notices.
  • Fixed group names (commas in names are treated by MailChimp as a delimiter indicating multiple groups).

1.7 | 2012-07-03

  • Fixed issue with some Mapped Fields not being passed (Entry Date, User IP, Source Url, Form Title).
  • Added new conditional logic options (greater than, less than, contains starts with, ends with) and support for other conditional fields.
  • Fixed notices.
  • Fixed issue when testing if email is already in the list.

1.6.3 | 2012-03-13

  • Added logging.
  • Fixed notices.
  • Fixed issue with single quotes on feed edit screen creating javascript errors.

1.6.2 | 2012-03-01

  • Fixed issue with sack script being initialized with an incorrect admin url.
  • Fixed issue that causing conflicts with feeds created by older versions of the plugin.

1.6.1 | 2012-01-20

  • Fixed issue that caused warnings to be displayed on feeds created by older versions.

1.6 | 2012-01-05

  • Fixed issue where RG_CURRENT_PAGE constant was not available when GF is deactivated.
  • Fixed noticed caused where $api variable not declared.
  • Added support for MaiChimp Groups so that subscribers can be assigned to a group when added to a list.
  • Added Form Title to the list of fields to be mapped.
  • Updated procedure that gets the MailChimp lists so that more than 25 lists are returned (up to 100).
  • Added integration with PayPal so that subscribers can be added only when payment is received.

1.5 | 2011-06-23

  • Updated API Wrapper to 1.3 (mini).
  • Removed blank strings from POT file to prevent error messages in Poedit.

1.4 | 2011-04-25

  • Cleaned up notices.
  • Fixed issue when using Opt-in condition on a field with multiple single quote characters in the label.
  • Fixed issue when creating a feed using forms with HTML markup in field labels.


  • Cleaned up notices.


  • Added "Cancel" button to Edit page and updated "Save" and "Update" button verbiage.

1.3.2 | 2011-02-06

  • Fixed issue with MailChimp lists being displayed as blank values. Taking into account different data formats returned by the API.

1.3.1 | 2010-12-15

  • Using new MailChimp PHP API wrapper (v. 1.2.6) when authenticating via an API Key.

1.3 | 2010-12-15

  • Added support for authentication via MailChimp API Key.

1.2 | 2010-12-15

  • Fixed issue with automatic upgrade on WP 3.0.


  • Adding MailChimp capabilities to admin role upon plugin activation.


  • Added MailChimp icon.
  • Renamed "Contact List" to "MailChimp List".


  • Changed text on list page when settings haven't been configured.
  • Created POT file.

0.2 | 2010-12-15

  • Map Fields column headers to ?List Fields? and ?Form Fields? and bol.
  • Rename button to "Save Feed" for a new feed and "Update Feed" for an existing one.
  • Settings page subnavigation to look like "Edit Forms" subnav (i.e. All | Active | Inactive) with no pipe at the end.
  • Try adding menu item between Entries and Settings.
  • Move "Add Feed" to top right (like posts page) and rename to "Add new".

0.1 | 2010-12-15

  • Split logic from Feeds Add-On.
  • Implemented automatic upgrade.
  • Implemented list page checkboxes (for bulk actions).
  • Implemented active/inactive icons on list page.