Automate Square & Mailchimp

Stop paying for mismatched spreadsheets. Sync data between Square and Mailchimp in real-time, so you can manage your operations without the busywork.

Get This Workflow Built

Custom API Integration

Secure Data Transfer

Done-For-You Setup

How the Data Flows

graph LR
    subgraph Source ["Square"]
        T1(["Completed Payment"])
    end
    
    subgraph Middleware ["Enterprise Integration Core"]
        W[CRON API
Poller] --> V{Validation
& Auth}
        V -->|Fail| DLQ[Dead Letter
Queue]
        V -->|Pass| Map[Data Mapping
& Transformation]
        Map --> Retry[Rate Limiting
& Retries]
    end
    
    subgraph Target ["Mailchimp"]
        A1(["Add Note to Subscriber"])
    end

    T1 -->|JSON Payload| W
    Retry -->|Authenticated API POST| A1

    style Source fill:transparent,stroke:#cbd5e1,stroke-dasharray: 5 5
    style Target fill:transparent,stroke:#cbd5e1,stroke-dasharray: 5 5
    style Middleware fill:#f8fafc,stroke:#94a3b8,stroke-width:2px
    style T1 fill:#3b82f6,stroke:#fff,stroke-width:2px,color:#fff
    style W fill:#1f2937,stroke:#fff,stroke-width:1px,color:#fff
    style V fill:#1f2937,stroke:#fff,stroke-width:1px,color:#fff
    style Map fill:#1f2937,stroke:#fff,stroke-width:1px,color:#fff
    style Retry fill:#1f2937,stroke:#fff,stroke-width:1px,color:#fff
    style DLQ fill:#ef4444,stroke:#fff,stroke-width:1px,color:#fff
    style A1 fill:#e11d48,stroke:#fff,stroke-width:2px,color:#fff

When Square transactions occur, the sales data is not automatically reflected in Mailchimp, leading to missed marketing opportunities. For instance, if a customer makes a purchase but their email address is not synced to Mailchimp, the marketing team cannot target them with follow-up campaigns. This results in manual data entry by the marketing team, wasting hours each week as they cross-reference sales reports from Square with their Mailchimp lists to ensure customer engagement.

Top Ways to Automate Square & Mailchimp

Automated Customer Sync: Effortlessly sync customer data between Square and Mailchimp, ensuring that your marketing lists are always up-to-date with the latest purchases and customer interactions.
Targeted Email Campaigns: Create dynamic segments in Mailchimp based on Square transaction data, allowing you to send personalized promotions to customers based on their purchase history and preferences.
Sales Performance Tracking: Automatically track the effectiveness of your email campaigns in driving sales through Square, providing insights into customer behavior and campaign ROI for informed decision-making.

How to Build the Square → Mailchimp Sync

Set up a webhook in Square to listen for the 'payment.updated' event. This will trigger whenever a payment is processed.
In the webhook payload, extract the 'customer.email' and 'transaction.amount' fields from the JSON data.
Use the Mailchimp API endpoint POST https://.api.mailchimp.com/3.0/lists//members to add or update the customer in your Mailchimp audience.
Construct the payload for the Mailchimp API with the extracted email and transaction data, ensuring to set the 'status' to 'subscribed' and include any additional fields you want to capture.
Test the integration by processing a payment in Square and verifying that the customer appears in Mailchimp with the correct transaction details.

Developer Warnings & API Gotchas

Ensure that the 'customer.email' field is always present in the Square webhook payload; otherwise, Mailchimp will reject the API call.
Be cautious with the 'status' field in the Mailchimp payload; if set incorrectly, it may prevent existing customers from being updated properly.
Consider the data format for 'transaction.amount'; Mailchimp may require specific formatting for custom fields, so validate the data before sending.

Supported API Operations

We leverage official, stable endpoints to ensure secure data transfer. No deprecated legacy routes.

When this happens in Square... Completed Payment

Do this in Mailchimp Add Note to Subscriber
When this happens in Square... Fetch Custom Actions

Do this in Mailchimp Add Subscriber to Tag
When this happens in Square... Item Variation

Do this in Mailchimp Add/Update Subscriber
When this happens in Square... List Appointment Service

Do this in Mailchimp Add/Update Subscriber
When this happens in Square... Locations

Do this in Mailchimp Archive Subscriber

SyncMatrix Experts

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I can see you're looking at mapping Square to Mailchimp. Tell me about your current setup—what's the specific bottleneck you're trying to automate right now?