S2S tracking is not magic: why “100% accurate” still requires reconciliation

S2S tracking is not magic: why “100% accurate” still requires reconciliation

Server-to-server postbacks remove browser failure points, but they do not make reporting perfect. Conversions can be delayed, duplicated, rejected, reversed, or matched to another click. Your tracker and the network may also use different attribution windows or status rules.

Reconcile with four checks:
• Store the click ID and conversion ID in both systems.
• Make retries idempotent, so one conversion cannot count twice.
• Log the request, response, status code, and timestamp.
• Compare the same time zone, event type, status, and reporting window.

Never compare totals blindly. Sample conversion IDs from each system and search for them in the other. Label gaps as missing, duplicate, delayed, rejected, or reversed. Each category points to a different fix, from payload handling to attribution settings.

S2S is a delivery mechanism, not a truth layer. Keep reconciliation in your tracking routine and investigate by conversion ID before changing the entire setup.