Migrating from Klaviyo

This guide walks you through migrating from Klaviyo to Sender, covering subscriber data, templates, automations, and domain setup.

Before You Start

• An active Sender account with access to the dashboard.
• Admin, Owner, or Analyst access to your Klaviyo account (required for exporting lists and segments).
• A list of what you plan to migrate: subscribers, templates, automations, signup forms, suppression lists, and sending domains.
• Exported files stored locally before importing into Sender — do not delete anything from Klaviyo until migration is fully tested.
• Recommended migration order: domains → subscribers and suppression lists → custom fields → templates → automations → forms → test → deactivate Klaviyo.

Migration Checklist

Subscribers — In Klaviyo, go to Audience → Lists & segments, click into each list, open the Manage list dropdown, and select Export list to CSV. In Sender, go to Subscribers → Add subscribers → Import from a file and upload the exported CSV file.

Custom fields — In Klaviyo, custom properties are included in your CSV export when you choose to export all properties. In Sender, go to Subscribers → Fields → Create new field to create matching custom fields before importing, so columns map correctly during the import process.

Tags and groups — Klaviyo uses lists and segments to organize contacts. In Sender, the equivalent is Groups. Go to Subscribers → Groups → Create new group to recreate your Klaviyo lists as groups. Assign subscribers to groups during import.

Email templates — In Klaviyo, go to Content → Templates, click the additional options menu next to a template, and select Export to download the HTML. In Sender, create a new campaign via Email campaigns → New campaign, choose the Custom HTML design type on the Design step, and paste the exported HTML into the code editor.

Automations — Klaviyo flows cannot be exported as files. Document the trigger, filters, timing, and email content for each flow. In Sender, go to Automations → Create new workflow to rebuild each automation from scratch.

Signup forms — Klaviyo forms cannot be exported. Note the form type (popup, embedded), fields collected, and connected list for each form. In Sender, go to Forms → Create a new form to recreate them as pop-ups or embedded forms.

Suppression lists (unsubscribes and bounces) — In Klaviyo, go to Audience → Profiles, click Suppressed Profiles in the upper right, then click Export CSV. Import this file into Sender with the correct unsubscribed status to protect your sender reputation.

Sending domain authentication — Klaviyo's DNS records will not work for Sender. In Sender, go to Account settings → Domains → Add domain and configure the new SPF, DKIM, and DMARC records that Sender provides in your domain's DNS settings.

Steps to Migrate Subscribers

Step 1 — Export your subscriber lists from Klaviyo

In Klaviyo, navigate to Audience → Lists & segments. Click into the list you want to export. Open the Manage list dropdown in the upper right and select Export list to CSV. Choose whether to export all properties or only specific ones. The export file will be available under Settings → Other → Downloads within a few minutes. Repeat this process for each list you want to migrate.

Step 2 — Prepare your file and create matching fields in Sender

Open your exported CSV file and review the column headers. In Sender, go to Subscribers → Fields and check that each column from your Klaviyo export has a matching field. If your Klaviyo data includes custom properties (such as company name or purchase date), click Create new field to add them before importing. Also go to Subscribers → Groups → Create new group to create groups that correspond to your Klaviyo lists.

Step 3 — Import subscribers into Sender

In Sender, go to Subscribers → Add subscribers → Import from a file. Drag and drop your CSV file or click Import file to upload it. Supported file types are .csv, .txt, and .xlsx with a maximum size of 64MB. On the next screen, map each column from your file to the corresponding field in Sender. Select the group to assign subscribers to, then confirm the import.

Step 4 — Import your suppression list

In Klaviyo, go to Audience → Profiles, click Suppressed Profiles, and click Export CSV. Import this file into Sender through Subscribers → Add subscribers → Import from a file. Ensure that unsubscribed and bounced contacts retain their suppressed status so Sender does not send emails to contacts who have opted out.

What Cannot Be Migrated

Campaign performance history — Open rates, click rates, send history, and revenue attribution data from Klaviyo cannot be transferred to Sender. Export and save any historical reports from Klaviyo's Analytics tab before deactivating your account. New performance data will begin tracking in Sender from your first send.

Flow and automation analytics — Performance data for individual Klaviyo flows (send counts, conversion data, revenue per flow) cannot be moved. Export flow analytics from Klaviyo before migration if you need to retain them for reference.

Form submission history — Klaviyo tracks form views, submissions, and conversion rates for each signup form. This data does not transfer. Your forms in Sender will start collecting fresh analytics from the moment they go live.

Segments with behavioral conditions — Klaviyo segments built on event-based conditions (such as purchase history, site activity, or email engagement) cannot be exported as dynamic segments. Export these as static CSV lists and import them as groups in Sender. Rebuild dynamic segments in Sender under Subscribers → Segments using Sender's segment conditions.

Klaviyo-specific integrations and tracking scripts — Direct integrations between Klaviyo and your ecommerce platform or other tools do not carry over. Set up new integrations in Sender. Remove Klaviyo's tracking snippets from your website after migration is complete.

Post-Migration Verification

Subscriber count match — Compare the total number of active subscribers in each Klaviyo list with the corresponding group in Sender under Subscribers → Groups. The Active count in Sender should match the count from your Klaviyo export.

Custom field mapping — Open several individual subscriber profiles in Sender by clicking on them under Subscribers. Verify that custom field values (such as first name, last name, and any custom properties) imported correctly and appear in the expected fields.

Suppression list accuracy — Confirm that unsubscribed and bounced contacts show the correct status in Sender. Filter subscribers by Email status on the Subscribers page to verify that suppressed contacts are not marked as active.

Domain authentication — Go to Account settings → Domains and confirm that your domain shows green checkmarks under Ownership confirmed and Authentication. Click Recheck DNS records if the status has not yet updated.

Test email delivery — Create a test campaign in Email campaigns → New campaign and send it to yourself using Send test email on the Design step. Verify the email arrives in your inbox, displays correctly, and that links and images work.

Automation trigger test — Activate one automation in Automations and trigger it with a test subscriber. Verify that the workflow fires correctly and the subscriber receives the expected email.

Form rendering — Publish a form from Forms, visit the page where it is embedded or triggered, and verify that it appears correctly and successfully adds a test subscriber to the assigned group in Sender.

Migration Tips

Migrate domains first — Verify your sending domain in Sender under Account settings → Domains before importing subscribers or sending any campaigns. DNS propagation can take up to 48 hours.

Export everything from Klaviyo before canceling — Download all lists, suppression lists, templates, and analytics reports before you downgrade or close your Klaviyo account. Once your account is closed, you may lose access to this data.

Import suppression lists early — Importing unsubscribed and bounced contacts into Sender before sending any campaigns prevents accidental sends to opted-out contacts and protects your sender reputation.

Test with a small group first — Before sending campaigns to your full list, send to a small test group to confirm that templates render correctly, personalization fields populate, and links work as expected.

Keep Klaviyo active during migration — Do not cancel your Klaviyo plan or delete flows and forms until you have fully tested your Sender setup and confirmed everything works.

Common Issues

Import fails or shows errors → This usually happens when the CSV file has formatting issues, such as extra commas, mismatched column counts, or encoding problems. Open the file in a text editor, remove any blank rows or special characters, save as UTF-8 encoded CSV, and try the import again.

Subscriber count is lower after import → Sender may deduplicate contacts based on email address. If the same email appeared in multiple Klaviyo lists, it will appear once in Sender. Duplicate emails within a single file are also merged. Check the import summary for skipped or duplicate entries.

Custom fields did not map correctly → If custom field data appears in the wrong column or is missing, the column headers in your CSV may not have matched the field names in Sender. Go to Subscribers → Fields, verify field names, and re-import the file with corrected column headers.

Domain authentication not passing → DNS record changes can take up to 48 hours to propagate. Verify that you added the correct SPF, DKIM, and DMARC records provided by Sender to your domain's DNS settings. Click Recheck DNS records under Account settings → Domains after allowing time for propagation.

Emails landing in spam after migration → A new sending platform means your domain is building reputation with a new sending infrastructure. Start by sending to your most engaged subscribers, gradually increase volume over several days, and ensure your domain authentication is fully verified.

FAQs

How long does migration typically take? This depends on the volume of data and the number of assets to recreate. Subscriber imports take minutes. Recreating templates, automations, and forms may take several hours to a few days depending on complexity. Plan ahead and test before deactivating Klaviyo.

Will I lose my email sending history? Campaign performance data (open rates, click rates, send history) from Klaviyo cannot be transferred to Sender. Export and save your historical reports from Klaviyo before migrating. New performance data will begin tracking in Sender from your first send.

Should I import unsubscribed contacts? Yes. Import your suppression list (unsubscribed and bounced contacts) into Sender with the correct status to avoid sending to contacts who have opted out. This protects your sender reputation and ensures compliance.

Do I need to re-verify my sending domain in Sender? Yes. Even if your domain was verified in Klaviyo, you need to add it in Sender under Account settings → Domains and configure the SPF, DKIM, and DMARC records that Sender provides. Klaviyo's DNS records will not work for Sender.

Can I keep both platforms running during migration? Yes. Keep Klaviyo active until you have fully tested your Sender setup — subscriber data, templates, automations, forms, and domain authentication. Only deactivate Klaviyo after verifying everything works in Sender.

Can I import my Klaviyo email templates directly into Sender? You can export the HTML of each template from Klaviyo under Content → Templates → additional options → Export. In Sender, create a campaign with the Custom HTML design type and paste the HTML code into the editor. Templates built with Klaviyo's drag-and-drop builder will need design adjustments, as Klaviyo-specific template syntax is not compatible with Sender's editor.

Can Sender's support team help with migration? Check Sender's support options for assisted migration services. Some plan tiers may include migration assistance. Contact Sender support with details about your source platform and the volume of data to discuss options.