> For the complete documentation index, see [llms.txt](https://docs.inogic.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.inogic.com/marketing4dynamics/features/subscription-status-sync-opt-in-opt-out-between-mailchimp-and-microsoft-dynamics-365.md).

# Subscription Status Sync (Opt-In/Opt-Out) Between Mailchimp and Microsoft Dynamics 365

Marketing4Dynamics ensures seamless synchronization of subscription (opt-in/opt-out) status between Mailchimp and Dynamics 365, while maintaining compliance with consent and email marketing regulations.

In Mailchimp, the opt-in status determines whether a contact has permitted to receive email communications. When a contact subscribes (or confirms via double opt-in), their status is marked as Subscribed.

With Marketing4Dynamics, this subscription data is synchronized back to Dynamics 365, allowing you to track and manage customer consent directly within CRM.

**How It Works:**

* When a contact unsubscribes in Mailchimp, the updated status is synced back to Dynamics 365 via:

1. Audience Sync
2. Campaign Sync
3. Marketing List Sync

* The subscription status is updated in CRM and can be viewed in the Subscriber Status field (Subscribed/Unsubscribed), as shown in the screenshot.

<figure><img src="/files/O3NKfOPrgNI9AbG3owBr" alt=""><figcaption></figcaption></figure>

* If a contact is re-subscribed in Mailchimp, running the sync again updates the status in Dynamics 365 accordingly.
* New contacts created in Dynamics 365 are added as Subscribed members in Mailchimp during synchronization.
* Marketing4Dynamics does not re-subscribe unsubscribed contacts automatically, ensuring strict adherence to Mailchimp policies and data privacy regulations.

**Campaign Sync Behavior:**

In addition to audience and list sync, Marketing4Dynamics also ensures subscription alignment during campaign syncing:

* Campaign activities (such as sends, opens, clicks, and unsubscribes) are retrieved from Mailchimp.
* Based on these activities, the subscription status is mapped and updated appropriately in Dynamics 365.
* This ensures that engagement data and consent status remain fully synchronized across both platforms.

**OOB Field Mapping in Dynamics 365:**

Marketing4Dynamics also updates standard (out-of-the-box) fields in Dynamics based on Mailchimp subscription status.\
\
Specifically, the Out-of-the-Box (OOB) fields **“Do Not Allow Bulk Emails”** and **“Send Marketing Materials”** on the Contact and Lead entities are updated based on the subscription status from Mailchimp. For example, when a contact **subscribes or unsubscribes** in Mailchimp, upon synching the corresponding fields in Dynamics 365 CRM are updated to reflect the correct marketing communication preference.

<figure><img src="/files/HyCbKVKE5KHGtwH0yVkw" alt=""><figcaption></figcaption></figure>