How to Connect 
Mailchimp + 
Klaviyo: Step-by-Step Integration & Automation Guide (2026)
A complete blueprint for automating workflows between Mailchimp and Klaviyo using native connectors, Webhooks, or Zapier/Make.
- Connection
- Middleware
- Zapier Required
- Setup time
- 20–30 minutes
- Difficulty
- Medium
When & why to run Mailchimp with Klaviyo
General-purpose email vs. ecommerce powerhouse.
Mailchimp is a general, beginner-friendly email platform for any small business; Klaviyo is purpose-built for ecommerce, with deep Shopify data, SMS, and revenue-driven automation. Choose Mailchimp for simple, broad email marketing; choose Klaviyo if you run an online store and want purchase-behavior-driven email and SMS.
Automation Blueprints — make them work together
The real payoff is the stack. These are concrete Mailchimp ↔ Klaviyo workflows worth building.
New subscriber → sync profile
New Subscriber
During migration
Add Profile
Move contacts between platforms during a migration.
New profile → sync audience
New Profile
Has matching audience
Add to Audience
Keep audiences aligned across tools.
Setup steps
The Zapier/Make path, start to finish.
- 1
Create a Zapier or Make account and connect both Mailchimp and Klaviyo (authorize each via OAuth).
- 2
Create a new Zap/Scenario with the trigger — Mailchimp: New Subscriber.
- 3
Add a filter for the condition (During migration) so the workflow only fires when it should.
- 4
Add the action in Klaviyo (Add Profile) and map the fields from the trigger data.
- 5
Test with a live record, verify the result, then turn the automation on and repeat for the other workflows.
Edge cases & rate limits
What breaks in production — plan for these before you scale.
- Field mapping: Mailchimp and Klaviyo fields rarely map 1:1 — normalize dates, currencies, and dropdown/picklist values explicitly.
- Pick a source of truth per field to avoid two-way syncs overwriting each other in a loop.
- Mailchimp: Key tools (journeys, advanced segmentation, more seats) are gated to higher tiers, and send caps are fixed multiples of your contact count.
- Klaviyo: Pricing scales steeply with active profiles — cost grows automatically as your list expands, with no flat rate.
- Klaviyo: SMS/MMS credits are billed separately on top of the profile price and can dwarf the base cost for heavy senders.
- Zapier/Make task usage is metered — high-volume workflows can burn through your monthly task/operations quota, so batch where possible.
- Watch API rate limits on bulk backfills — throttle or batch to stay under each tool's per-second/per-minute caps.