Hi, Thank you for reaching out to the Google Ads API support team.
I understand that you are tracking conversions using GTM with the “Google Ads Conversion Tracking” tag on the client-side and Google Ads API (uploadClickConversions) in the backend. Please find the answers for your questions below: 1. If we fire a GTM conversion tag with a transaction_id, and also send the same conversion via uploadClickConversions with the same orderId, will Google automatically deduplicate and count only one conversion? Kindly note that, as per this article both the transaction Id and order id are same. The term "order ID" is used instead of transaction ID in the context of offline conversions, including offline conversion adjustments and enhanced conversions for leads. So, If you upload same conversion twice, Google ads recognizes and omits the duplicate if two conversions share the same ID. Based on the question asked, it seems like you are thinking that two conversions are uploaded when a transaction Id is fired and when you upload the conversions using Google Ads API. Kindly note that all this comes under the same process and the conversion is being uploaded only once. 2. In case transaction_id / orderId is not present, does Google fallback to deduplication based on gclid, conversion_action, and conversion_time? Yes, If a transaction_id or order Id is not present or is empty, Google Ads will indeed attempt to deduplicate conversions based on a combination of gclid, conversion_action and conversion_time. You can find the information about this in this FAQ. 3. Are there any required conditions or best practices to ensure deduplication works reliably when using GTM and API together? For the most accurate and reliable conversion tracking, you should always prioritize and consistently implement unique transaction_id/orderId values for every conversion. This ensures that real unique conversions are counted once, and other conversions with same ID's are ignored. Thanks, Google Ads API Team Feedback How was our support today? [2025-06-23 12:09:18Z GMT] This message is in relation to case "ref:!00D1U01174p.!500Ht01rfwVP:ref" (ADR-00315314) -- -- =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ Also find us on our blog: https://googleadsdeveloper.blogspot.com/ =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ You received this message because you are subscribed to the Google Groups "AdWords API and Google Ads API Forum" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/adwords-api?hl=en --- You received this message because you are subscribed to the Google Groups "Google Ads API and AdWords API Forum" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/adwords-api/RYZ57000000000000000000000000000000000000000000000SYB5RI00-A3wu-3KS2G5H-gUYz3fVw%40sfdc.net.
