Connecting Klaviyo to SendX brings your contacts, lists, and email templates into SendX so you can continue sending without rebuilding your audience or recreating your designs. Once connected, SendX keeps your data up to date automatically.
When you'd use this
You've been using Klaviyo for email marketing and want to move to or add SendX. This integration migrates your profiles, lists, and templates so you can send campaigns from SendX right away.
What data gets synced
When you connect Klaviyo, SendX imports the following:
Email templates — Klaviyo email templates are synced as SendX templates, prefixed with KLAVIYO_ so you can easily identify them.
Lists — All Klaviyo lists are created as SendX lists with the same names.
Profiles (contacts) — Email, first name, last name, company, and profile attributes are mapped to SendX contact fields. All other profile attributes are synced as custom fields.
Synced contacts are automatically tagged via_klaviyo so you can identify, filter, and segment them at any time.
Campaigns, flows, events, and segments are not synced — only templates, lists, and profiles are imported.
Before you start
Make sure you have:
An active Klaviyo account with profiles and at least one list
Ability to create a Private API key in Klaviyo
A SendX account with permission to manage integrations
Step-by-step setup
1. Click on your Profile in your Klaviyo dashboard.
2. Click on Settings.
3. Click on API keys.
4. Click Create Private API Key.
5. Give the key a name and select Read-Only Key.
6. Click Create.
7. Click the copy icon to copy your API key.
8. In your SendX account, go to Settings > Integrations and click New Integration.
9. Select Klaviyo from the dropdown, paste the API key, and click Save.
10. You're all set! The integration will begin syncing data. The time required depends on the number of profiles in your Klaviyo account.
After the initial sync, SendX checks for new and updated profiles and templates from Klaviyo every hour.
Important notes
Templates are prefixed KLAVIYO_. Synced templates appear in SendX with the prefix so you can identify where they came from.
Templates are created or updated. If a template with the same name already exists in SendX, it is updated with the latest HTML from Klaviyo.
Custom profile attributes become custom fields. Any Klaviyo profile attribute that doesn't map to a standard SendX field (email, name, company, IP) is created as a custom field in SendX.
Incremental sync for profiles and templates. After the initial import, only profiles and templates updated since the last sync are processed each hour.
Contacts are deduplicated by email. If a contact already exists in SendX, their record is updated — not duplicated.
Deleting the integration stops future syncs but does not remove contacts, lists, or templates already in SendX.
Common questions
How long does the initial sync take?
Small accounts typically sync within a few minutes. Larger accounts may take longer.
Will my existing SendX contacts be overwritten?
No. SendX merges by email address. Existing contacts are updated — nothing is deleted.
My Klaviyo profiles have custom attributes — will those sync?
Yes. Any attribute that doesn't match a standard SendX field is automatically created as a custom field in SendX.
Will my Klaviyo templates look the same in SendX?
The HTML content of each template is synced as-is. How it renders depends on whether the template uses Klaviyo-specific merge tags — you may need to update those to SendX merge tags before sending.
What happens if I delete the integration?
Contacts, lists, and templates already synced into SendX remain. Deleting the integration only stops future syncs.