---
title: "Send shoppers to Mailchimp"
description: "Shopper ID with Mailchimp: what's charged, what's supported, and how to connect it."
url: https://wholayer.com/help/destination-mailchimp
---

# Send shoppers to Mailchimp

> Shopper ID with Mailchimp: what's charged, what's supported, and how to connect it.

Category: Destinations

Included on the **Growth** plan and above.

## What you're charged
Before we charge, we check whether the shopper is already in your Mailchimp. New shoppers cost 2 credits, once; shoppers already there cost 1 credit, are never duplicated, and get a **WhoLayer Returning Shopper** event instead.

## What Mailchimp supports
- **Checks your list first:** yes.
- **Refunds bounces:** yes, bounces and spam complaints within 30 days.
- **Deliverability Guard:** the daily cap adjusts to your 7-day complaint and bounce rates.
- **Holdout report:** no, so nobody is held out and every new shopper is sent.

## Connect it
1. In Mailchimp, open **Profile → Extras → API keys** and create a key. It ends in your data center, like `-us21`.
2. Find the audience id under **Audience → Settings → Audience name and defaults**.
3. In WhoLayer, open **Destinations**, choose **Mailchimp**, and paste the key and audience id.
4. Click **Send test**. New shoppers are added to the audience as **non-marketing (transactional) contacts** with a "WhoLayer Shopper ID" tag, because they haven't opted in to your marketing. We never change the status of someone already in your audience.
5. Build a Customer Journey that starts on the **WhoLayer Shopper Identified** or **WhoLayer Returning Shopper** event.

## Good to know
- Mailchimp's orders API can't be read by date, so there's no holdout report.
- Deliverability Guard rates come from your campaign reports for the last 7 days.
- Refunds use members Mailchimp cleaned (hard bounces) and abuse reports on the audience.
- Opted-out people are never sent, and opt-outs take effect immediately.
- We encrypt your key when you save it and only ever show its last characters.

## Related

- [How Shopper ID works](https://wholayer.com/help/shopper-id-how-it-works.md)
- [Shopper ID and Klaviyo: what you're charged for, refunds, the daily cap, and the holdout](https://wholayer.com/help/shopper-id-klaviyo-guarantees.md)
- [Klaviyo schema: WhoLayer profile properties and events](https://wholayer.com/help/klaviyo-schema.md)
- [Your responsibilities when you use WhoLayer](https://wholayer.com/help/customer-obligations.md)