Klaviyo | Sync your contacts

The Sinch Engage platform offers a streamlined approach to contact management through its automated integration with Klaviyo.

Contact sync

Contact sync is a one-way automatic sync of contact information from Klaviyo to the Sinch Engage platform. This means any names, phone numbers, emails and opt-out status in your Klaviyo database will be securely imported into your Sinch Engage account - no manual uploads required.

These contacts are clearly marked as "KLAVIYO" in your contact list to easily distinguish them from contacts added via other sources.

Contact sync occurs every 24 hours - this pulls in the latest updates from your Klaviyo contacts list, including any changes or new entries and reflects them in your Sinch Engage account.

When an opt-out request is received from a recipient, Sinch Engage marks that contact as opted-out and also sends that status to the Klaviyo side. This update will then reflect in the 'SMS Consent status' of the Klaviyo contact.

Considerations when syncing contacts in Klaviyo

When syncing contacts with Klaviyo, there are several important factors to keep in mind to ensure a smooth and efficient process:

• Sync Duration: Due to Klaviyo API rate limits, syncing contacts can take approximately 2.5 hours per 100,000 contacts. Please plan your campaigns well in advance to accommodate this syncing time.
• Estimating Sync Time: The sync time is calculated based on the total number of Klaviyo profiles in your account, not just the contacts in the selected list from the Engage side. Therefore, estimate the completion time based on the total number of contacts in your Klaviyo database.
• Avoid Manual Contact Uploads: If you have enabled Klaviyo contact sync, avoid performing manual contact uploads. Manual uploads can interfere with the sync process, resulting in manually updated numbers not syncing properly or failing to pass back their opt-out statuses.
• Adding a New List: If you have made new lists since your last sync, you can modify contact sync for your existing Klaviyo connection and tick those new lists before hitting the manual sync button.
• Sending While Syncing: You can continue to send messages to your current lists while a new sync is in progress. The sync process updates your contacts at the end, allowing you to continue your campaigns without interruption.

Set up contact sync during installation

Getting started with contact sync is easy when you first connect your Klaviyo account to Sinch Engage. 

1. From the Sinch Engage platform, click on Extensions and then Integrations.
2. Locate the Klaviyo tile and click Install.

3. Enter the API Key from your Klaviyo account.

   

4. Choose which SMS Consent method is right for you.
   • Inferred Consent: Select this when a customer provides you with their phone number, your business has provided them with the reasonable expectation that they’ll receive SMS Marketing (without the need to expressly opt in). Sinch Engage will recognise these contacts as subscribed and update their subscription status as such.
   • Explicit Consent: Select this option when a customer provides you with their phone number. There's a reasonable expectation that, in providing their number, they'll receive SMS Marketing (without the need to expressly opt in). These profiles will therefore have the SMS consent status set as 'Never subscribed.’ Sinch Engage will recognize these contacts as "subscribed" and update their subscription status accordingly.
5. Click Connect.
6. Check the box to Sync my contacts from Klaviyo to Sinch Engage to enable contact syncing.
7. If you've got a large contact database in Klaviyo, you can keep the automatic syncing process efficient by only selecting the lists you plan to use for SMS campaigns. This reduces unnecessary data syncing and the need to consistently sync a high volume of data. To do this, select the checkbox next to the contact lists you want to sync with Sinch Engage.

8. Click Next.

   

9. To personalize your messaging, map the fields between Sinch Engage and Klaviyo. For each Sinch Engage platform field, select the corresponding Klaviyo field from the drop-down list. You can use the + Map more fields button to add custom fields.

   

   Note: Make sure the data types on both sides match e.g. Date field matches Date field, Number field matches Number field, Text field matches Text field.

   If you're unsure about the Klaviyo field type, map it to a Text type field in Sinch Engage platform as text fields can store any type of data and will prevent sync failures.

   Avoid typing incorrect field names (e.g. phoneNumber instead of Phone number) and mapping dates or numbers to incompatible field types.

   We recommend testing with a small contact list first to ensure your mapping works as expected.

10. The Klaviyo API only returns custom fields for synced contacts and a limited number of contacts overall. Since custom fields can vary per contact, not all fields are returned - meaning visibility is limited to only those retrieved via the sync. 

    If you don't see the correct Klaviyo field, navigate to the contact's profile and add custom property. 

11. Start typing the field name - if no default field matches, a new field name will be mapped based on your input e.g. typing 'Title' creates a field named 'Title' if it doesn't exist in the list.

    Note: Make sure the field name matches exactly as displayed in Klaviyo. Spelling, capitalization and spacing must be correct, otherwise the sync may fail for that field.

12. Click Update to complete the setup.
13. You'll get a confirmation screen when your Klaviyo account has been successfully connected. Depending on the number of contacts to import, you'll be notified as soon as it's complete by email. Click on Got it! to dismiss the confirmation pop-up.

Enable or modify contact sync for an existing Klaviyo connection

If you've already connected the Klaviyo portal to the Sinch Engage platform, you can enable contact sync or update your previously selected contact lists at any time. To do this:

1. In the Sinch Engage platform, click on Extensions and then Integrations from the left-side navigation bar.
2. Find the Klaviyo tile and click See details.
3. Make sure you're in the Contacts and map fields tab.
4. Change your checkbox selection next to your contact lists.

5. Click on Next.

   

6. To personalise your messaging, map the fields between Sinch Engage and Klaviyo. For each Sinch Engage platform field, select the corresponding Klaviyo field from the drop-down list. You can use the + Map more fields button to add custom fields.

   

   Note: Make sure the data types on both sides match e.g. Date field matches Date field, Number field matches Number field, Text field matches Text field.

   If you're unsure about the Klaviyo field type, map it to a Text type field in Sinch Engage platform as text fields can store any type of data and will prevent sync failures.

   Avoid typing incorrect field names (e.g. phoneNumber instead of Phone number) and mapping dates or numbers to incompatible field types.

   We recommend testing with a small contact list first to ensure your mapping works as expected.

7. The Klaviyo API only returns custom fields for synced contacts and a limited number of contacts overall. Since custom fields can vary per contact, not all fields are returned - meaning visibility is limited to only those retrieved via the sync. 

   If you don't see the correct Klaviyo field, navigate to the contact's profile and add custom property. 

   Start typing the field name - if no default field matches, a new field name will be mapped based on your input e.g. typing 'Title' creates a field named 'Title' if it doesn't exist in the list.

   Note: Make sure the field name matches exactly as displayed in Klaviyo. Spelling, capitalization and spacing must be correct, otherwise the sync may fail for that field.

8. Click Update to complete the setup.

Trigger manual contact sync with Klaviyo

By default, contact syncing between Klaviyo and the Sinch Engage platform happens every 24 hours. You may need to manually trigger contact sync if you need those updates sooner e.g. if you've just updated contact details in Klaviyo and want to use that information right away for an SMS campaign.

You can view your sync status and trigger a manual sync from:

• New Message screen

  

• All Contacts and Contact Lists screen

  

Contact sync duplicate handling

You can sync contacts from multiple supported integrations without creating duplicate records. This process keeps your contact data consistent, reduces manual cleanup and supports more accurate segmentation for multichannel messaging.

• Contacts with the same phone number will be merged during sync and tagged with a custom Source label in the Sinch Engage platform under contact properties e.g. "Mailjet", "Klaviyo".
• A single contact can belong to multiple source groups to enable better segmentation e.g. Contact A can be part of both "Mailjet A" and "Klaviyo A” groups.