Google Phases Out Offline Conversion Imports in Ads API, Moves to Data Manager API.

Google has announced a significant shift in how advertisers can upload offline conversion data to its advertising platform. Beginning on June 15, the company will discontinue support for the UploadClickConversions request in the Google Ads API for accounts that have not used the feature in the past 180 days. The change will affect two key areas: traditional offline conversion imports and enhanced conversions for leads. All other Google Ads API operations will continue to function normally.

What Is Changing?

For developers and marketing technology partners who rely on the Ads API to feed offline conversion data—such as phone calls, in‑store purchases, or form submissions—this announcement means a migration is required. The UploadClickConversions endpoint, which has been the standard method for uploading conversion events that occur outside the web journey, will no longer accept requests after the cutoff date. The only exception is for accounts that have been actively using the endpoint within the last six months; those accounts will retain access until the end of the current billing cycle.

Google’s official guidance is clear: move all offline conversion workflows to the Data Manager API. This newer API is positioned as a unified ingestion layer that supports a range of data types, including Customer Match lists, conversion imports, and other first‑party data sets. By consolidating these data streams, Google aims to streamline the data pipeline and enable more robust, AI‑driven measurement and optimization across its advertising ecosystem.

Why It Matters to Advertisers

Offline conversion data is the lifeblood of many performance‑based campaigns. It allows advertisers to see the full impact of their ads beyond the click, tying revenue, leads, and other key actions back to specific keywords, audiences, and creative assets. When this data stops flowing into Google Ads, several downstream effects can occur:

• Reporting gaps – Campaign dashboards will no longer display the true conversion volume, leading to incomplete performance insights.
• Attribution drift – Without offline conversions, the attribution model may over‑credit online touchpoints, skewing the perceived effectiveness of ad spend.
• Automated bidding impact – Smart bidding strategies rely on accurate conversion signals. A sudden drop in reported conversions can cause the algorithm to misinterpret campaign health, potentially raising costs or lowering return on ad spend.
• Compliance and privacy – The Data Manager API is designed to work with Google’s privacy‑first data handling practices, ensuring that first‑party data is used responsibly and in line with evolving regulations.

In short, failing to migrate in time could lead to a cascade of performance issues that affect both short‑term results and long‑term strategic planning.

How to Transition to the Data Manager API

While the migration may sound daunting, Google has provided a clear roadmap. Below is a step‑by‑step checklist that developers and agencies can follow to ensure a smooth transition:

1. Audit Existing Workflows – Identify all instances where UploadClickConversions is called, including custom scripts, third‑party integrations, and automated pipelines.
2. Review Data Requirements – Map the fields currently being sent (e.g., conversion name, value, timestamp, click ID) to the corresponding fields in the Data Manager API’s conversion import schema.
3.