Klaviyo & Mailchimp — Subscriber Sync
Keep your Klaviyo profiles and Mailchimp lists in sync with your store automatically.
Klaviyo
Prerequisites
- A Klaviyo account
- A Klaviyo Private API key with Full Access or at minimum Profiles: Write and Events: Write
Get your Klaviyo API key
- Log into Klaviyo → Settings → API Keys
- Click Create Private API Key
- Name it "LaunchStore" and grant the required scopes
- Copy the key
Connect Klaviyo
- Go to Settings → Integrations → Klaviyo
- Paste your Private API key
- Click Save & Test
Available Klaviyo actions
Identify Profile
Creates or updates a profile in Klaviyo with customer attributes.
Recommended trigger: customer.created or order.created
Common field mappings:
| Klaviyo field | Event field |
|---|---|
email | customer.email |
first_name | customer.first_name |
last_name | customer.last_name |
phone_number | customer.phone (E.164 format) |
If a profile with the same email already exists, Klaviyo merges the data.
Track Event
Records a custom event against a Klaviyo profile. Use this to trigger Klaviyo flows.
Recommended trigger: order.created, order.fulfilled, order.refunded
Common field mappings:
| Field | Value |
|---|---|
event | "Placed Order" / "Fulfilled Order" / "Refunded Order" |
customer_properties.email | order.email |
properties.order_id | order.id |
properties.value | order.total / 100 |
properties.items | order.items (array) |
Example workflow: new customer → Klaviyo
customer.created
└─ Klaviyo: Identify Profile (email, name, phone)
This keeps your Klaviyo profile list in sync. Use this as the entry point into your Klaviyo Welcome Series flow.
Mailchimp
Prerequisites
- A Mailchimp account
- A Mailchimp audience (list) ID
- A Mailchimp API key
Get your Mailchimp API key
- Log into Mailchimp → Account → Extras → API keys
- Click Create A Key
- Copy the key
Get your Audience ID
- Go to Audience → Manage Audience → Settings
- Under Audience ID, copy the value (format:
abc123de45)
Connect Mailchimp
- Go to Settings → Integrations → Mailchimp
- Enter your API key
- Click Save & Test
Available Mailchimp actions
Add Subscriber
Adds a new subscriber to a Mailchimp audience.
Recommended trigger: customer.created
Common field mappings:
| Field | Value |
|---|---|
listId | Your Mailchimp Audience ID |
email_address | customer.email |
status | "subscribed" |
FNAME | customer.first_name |
LNAME | customer.last_name |
Update Subscriber
Updates an existing subscriber's data.
Recommended trigger: order.created (to update purchase activity tags)
| Field | Value |
|---|---|
listId | Your Mailchimp Audience ID |
email_address | order.email |
tags | ["customer", "purchased"] |
Example workflow: order → Mailchimp tag
order.created
└─ Mailchimp: Update Subscriber (add "purchased" tag)
This tags purchasing customers in Mailchimp so you can target them separately from subscribers who haven't bought yet.
Klaviyo vs Mailchimp — which should I use?
| Klaviyo | Mailchimp | |
|---|---|---|
| Best for | E-commerce flows, revenue analytics | General email marketing, newsletters |
| Profile tracking | Full purchase history, predicted CLV | Basic subscriber tags |
| Pricing | Free up to 500 contacts | Free up to 500 contacts |
If you're running an e-commerce store, Klaviyo's Identify Profile + Track Event combination gives you more segmentation power. Mailchimp's Add Subscriber is simpler and works well for newsletter opt-ins.