The Klaviyo Data Import Tool transfers your contact list and segments from Klaviyo to Omnisend, including email addresses, phone numbers, subscription statuses, custom properties, consent records, and segment definitions.
Contacts sync in batches of 500 every 5 seconds, so a 10,000-contact list takes approximately 2 minutes. Supported segments migrate automatically. Follow this guide to connect the tool and sync your data.
When to Use This Tool
Use the Klaviyo Data Import Tool if you're migrating contact and segment data yourself.
💡 If you've requested our free Kickstart service (available for $250+ monthly plans), our team will handle contact and segment import for you – you don't need to follow these steps.
This tool transfers contact information (emails, phone numbers, names, properties, consent) and segments. To migrate workflows, forms, and templates, see our Migrate from Klaviyo to Omnisend guide.
Setup Process
Step 1. In Omnisend, click Apps in the top-right corner.
Step 2. Find the Klaviyo Data Import Tool using the search box and click the Connect now button.
Step 3. You'll need to enter a Private API key generated in your Klaviyo account.
To generate one, keep the Omnisend tab open and:
Log in to your Klaviyo account.
Go to Settings → API Keys. Alternatively, click the following link: API Keys.
Once you're in, click Create Private API Key.
Select Full Access Key as the Access Level. Name your API key (e.g., 'Omnisend integration') and click Create.
💡 See Klaviyo's guide: How to create a private API key.
Once you're done, copy the API key.
Step 4. Go back to Omnisend, paste the API Key, and click Connect.
Step 5. Click Sync contacts & segments.
This syncs:
Contacts in batches of ~500 every 5 seconds.
Segments automatically.
Note: This integration doesn't sync contacts in real-time. If you're still using Klaviyo, manually initiate sync again to refresh contact information.
Verify the Sync
After clicking Sync contacts & segments:
You'll see Contact sync in progress on the button and status card.
When complete, the status updates to Completed (green badge) and shows your last sync date.
Once the sync is done, the tool displays:
Contacts Import
Contacts last synced: Number of contacts imported in the most recent sync.
Contacts with tags updated: Number of contacts assigned tags from Klaviyo segments and lists.
Status: Completed (green) or In Progress.
Last updated: Timestamp of most recent sync.
All imported contacts appear immediately in Audience → Contacts with the tag klaviyo_import_app.
Segments Migration
Below the Contacts Import card, you'll see a Segments Migration table with:
Kaviyo Segment: The name of the segment in Klaviyo.
Status:
Migrated ✅ – Segment successfully synced.
Failed ❌ – Segment uses unsupported filters or properties that cannot be recreated in Omnisend.
Omnisend Segment: The name of the synced segment in Omnisend with a clickable link to open the segment.
Migration Date: The latest date of the segment sync.
💡 Tips:
Click a migrated segment name to view its contacts, edit conditions, or use it in campaigns.
For failed segments, learn how to recreate them manually in Omnisend.
What Data is Synced
The Klaviyo Data Import Tool syncs contacts and segments from Klaviyo to Omnisend.
Contacts
The following contact properties are imported:
Email address
Phone number
First name
Last name
Address
City
Country
klaviyo_last_active_date (custom property created in Omnisend with the value from Klaviyo)
All custom properties from Klaviyo with a klaviyo_ prefix (e.g.,
favorite_colorbecomesklaviyo_favorite_colorin Omnisend)Tag klaviyo_import_app added to all synced contacts
Subscription Statuses
Contact subscription statuses map as follows:
Contacts with subscribed status in Klaviyo are imported as Email/SMS subscribers in Omnisend. The opt-in date is set to the Klaviyo timestamp.
Contacts with never subscribed status in Klaviyo are imported as non-subscribers in Omnisend.
Contacts with an unsubscribed or suppressed status in Klaviyo are imported as unsubscribers in Omnisend. The opt-out date is added based on the Klaviyo timestamp.
Consent Records
An email consent record is added to the contact profile in Omnisend if:
The
consent timestampproperty exists in Klaviyo, andAt least one of the following fields isn't empty:
$consent_method,$source,$consent_form_id,$consent_form_version
An SMS consent record is added to the contact profile in Omnisend when the SMS consent timestamp exists in Klaviyo.
Segments
Segments sync when their conditions are supported by Omnisend:
Segment name - prefixed with [OS] in Omnisend.
Filters and conditions - when compatible with Omnisend's segment filters.
Contact count - recalculated in Omnisend based on synced contacts.
Segments using Klaviyo-specific features (e.g., predictive analytics) and other conditions that can't be recreated in Omnisend will appear as Failed in the Segments Migration table.
Reinitiate Manual Sync
The Klaviyo Data Import Tool doesn't sync contacts or segments in real-time. If you're still using Klaviyo while transitioning to Omnisend, you'll need to manually re-sync to update contact information and capture new segments.
To re-sync:
Step 1. In Omnisend, go to Apps → Connected Apps (or click here). Then, find the Klaviyo Data Import Tool and click Edit.
Step 2. Click Sync contacts & segments.
The sync will run again, importing:
New contacts added to Klaviyo since your last sync.
Updated contact properties (e.g., name changes, new custom fields).
New or modified segments.
💡 Tip: If you're running both platforms simultaneously, re-sync daily to keep your Omnisend audience up to date.
FAQ
Why did some of my segments fail to migrate?
Segments fail when they use advanced AND/OR combinations with unsupported fields, or Klaviyo-specific features (e.g., predictive analytics). You can manually recreate these segments in Omnisend using Audience → Segments → Create Segment.
Can I edit migrated segments in Omnisend?
Yes. Click the segment name in the Segments Migration table to open it in Audience → Segments, where you can view contacts, adjust conditions, or rename it.
How do I know which contacts came from Klaviyo?
All contacts imported via this tool are automatically tagged with klaviyo_import_app. You can filter by this tag in Audience → Contacts.
Do segments sync in real-time?
No. Like contacts, segments only sync when you manually click Sync contacts & segments. If you're still using Klaviyo, re-sync regularly to capture new segments.
Got questions? Message us in-app or send an email to [email protected]. We’re here 24/7.