Offline Conversion Tracking
Upload call conversions
An UploadCallConversion maps to the Import conversion source in the Google Ads UI followed by choosing Conversion from calls.
A mobile click-to-call click cannot be uploaded as a conversion if there is no Google forwarding number attached to the call. Without a Google forwarding number, there is no way Google can be sure that the click led to a call and then to a conversion. If a click is uploaded like this, it will be ignored by the conversion tracker.
Once you create an UploadCallConversion, you can use the OfflineCallConversionFeedService to upload conversions for calls. See Importing Call Conversions below for details.