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Migration strategy

Learn how to migrate to Klaviyo's new APIs.


v1/v2 legacy APIs are scheduled to retire on June 30, 2024.

Users of Klaviyo's v1/v2 APIs have until June 30, 2024 to migrate to our new APIs. At this time, our v1/v2 APIs will officially be retired. To learn more about Klaviyo’s API lifecycle, check out our updated API versioning and deprecation policy.

With Klaviyo’s new APIs, we’ve added improvements to our API functionality, new endpoints, and new features to some of our existing endpoints. Some general improvements include:

  • All endpoints implement JSON:API which provides a standardized pattern for querying multiple, related objects in a single API request (e.g., fetching profiles that have been created after a specified date).
  • All endpoints have been vetted to ensure adherence to consistent URL, request, and response syntactical standards.
  • The URL topology has been reorganized to promote strong-typing, clear resource separation, and consistency with the Klaviyo UI (see comparison chart).
  • There are explicitly-documented rate limits for all endpoints with standard, informative HTTP headers for retry control-flow.

Additionally, we’ve added several new endpoints improving our APIs, either by replacing and enhancing existing functionality or expanding our APIs with exciting, new endpoints. Some of these new APIs include, but are not limited to:

  • Bulk Profile Import API

    Our Profiles API now has support for creating and updating profiles via Spawn Bulk Profile Import Job. To learn more, see our Bulk Profile Import guide.

  • Coupons API

    Create coupons and coupon codes for use in messaging, view the coupons and coupon codes in your account, and create bulk jobs for coupon codes via our Coupons API.

  • Flows API

    Fetch flows, update flow statuses, and access related objects for flows via our Flows API.

  • Images API

    Upload new images to your account from an image file, retrieve one or more images from your account, and update an existing image's name and/or status with our Images API.

  • Reporting API

    Use our new Reporting API to query the same service that powers the Klaviyo app to get 1:1 matches of your campaign and flow data.

Not a developer? Here's what to do

If you’ve received communications about your account(s) using legacy v1/v2 APIs, there are still some actions you need to take before June 30th. The table below includes the most common ways Klaviyo accounts are interacting with legacy APIs and our recommended actions for each scenario.

If you are unsure whether or not any of the following apply to you, we recommend taking a few minutes to audit your API usage. The report generated by Klaviyo’s API audit tool will give you more insight into how your account is interacting with legacy APIs so you can determine your next steps.

You can also read through our user FAQs for more information.

My account is using a custom-built integration.Reach out to the developer who built your custom integration and inform them of the API retirement communications you received. They will need to follow the resources linked on this page (see Developer migration resources) to update their API usage.

If you are working with a Klaviyo agency partner for development, they have already been informed by Klaviyo that they will need to migrate to our new APIs. If you have any questions around their migration plans, please reach out to your agency contacts.
My account relies on Klaviyo-built integrations.Most Klaviyo-built integrations don't require any updates, though a few that include plugins/extensions do. If you are using one of the following integrations, consult the link for upgrade instructions:
Magento 1
Magento 2
Salesforce Commerce Cloud
My account uses a third-party integration built by a technology partner of Klaviyo.If your account uses a third party integration, no immediate action is required on your part. Klaviyo has notified all tech partners about the retirement deadline, and they will be working to update their integrations before June 30th. You may want to check in with your partner contacts or review their integration documentation for more information about upgrading to a compliant version of their integration if needed.

Next steps for developers

If you're a developer, follow any of the steps below that apply to your account:

I only interact with Klaviyo APIs on the client-side through klaviyo.js.No action is required – klaviyo.js is a JavaScript library fully managed by Klaviyo and is already compliant with our new APIs.
I interact with Klaviyo APIs through the use of a Klaviyo-built SDK.Ensure that you have upgraded to a stable version of your SDK, as the legacy versions of our SDKs will also be retired on June 30th.
I maintain a third-party integration that multiple Klaviyo customers rely on.Any code in your integration that calls a v1/v2 API endpoint must be updated. You must publish a new release of your integration using only the new APIs before June 30th. See Developer migration resources to get started.

Klaviyo is communicating with customers to inform them they may need to upgrade their installed integrations, but we recommend highlighting the need to upgrade in any documentation and/or communication channels you have for your users.
I maintain custom code on behalf of a Klaviyo customer that interacts directly with Klaviyo’s APIs.Any code that calls a v1/v2 API endpoint must be updated before June 30th. See Developer migration resources to get started.
I maintain code that I’ve already upgraded to interact with Klaviyo’s new APIs.Congratulations on fully migrating from our legacy APIs! No further action is necessary. Note that if you upgraded prior to the 2023-07-15 revision, we recommend learning about the breaking changes released since then. It’s also best practice to plan your next upgrade well in advance of the deprecation timeline outlined in our API versioning and deprecation policy.

Developer migration resources

We have migration-specific and general API tools and guides that will help you through your migration process. Consult the resources below for more information:


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